Issue title: In SQS FIFO, task consumption temporarily stops when a large number of workers are started
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# Checklist
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* [ ] I have verified that the issue exists against the `master` branch of Celery.
* [ ] This has already been asked to the [discussion group](https://groups.google.com/forum/#!forum/celery-users) first.
* [x] I have read the relevant section in the
  [contribution guide](http://docs.celeryproject.org/en/latest/contributing.html#other-bugs)
  on reporting bugs.
* [x] I have checked the [issues list](https://github.com/celery/celery/issues?q=is%3Aissue+label%3A%22Issue+Type%3A+Bug+Report%22+-label%3A%22Category%3A+Documentation%22)
  for similar or identical bug reports.
* [x] I have checked the [pull requests list](https://github.com/celery/celery/pulls?q=is%3Apr+label%3A%22PR+Type%3A+Bugfix%22+-label%3A%22Category%3A+Documentation%22)
  for existing proposed fixes.
* [ ] I have checked the [commit log](https://github.com/celery/celery/commits/master)
  to find out if the bug was already fixed in the master branch.
* [x] I have included all related issues and possible duplicate issues
  in this issue (If there are none, check this box anyway).

## Mandatory Debugging Information
* [ ] I have included the output of ``celery -A proj report`` in the issue.
    (if you are not able to do this, then at least specify the Celery
     version affected).
* [ ] I have verified that the issue exists against the `master` branch of Celery.
* [x] I have included the contents of ``pip freeze`` in the issue.
* [ ] I have included all the versions of all the external dependencies required
  to reproduce this bug.

## Optional Debugging Information
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Try some of the below if you think they are relevant.
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* [ ] I have tried reproducing the issue on more than one Python version
  and/or implementation.
* [ ] I have tried reproducing the issue on more than one message broker and/or
  result backend.
* [ ] I have tried reproducing the issue on more than one version of the message
  broker and/or result backend.
* [ ] I have tried reproducing the issue on more than one operating system.
* [ ] I have tried reproducing the issue on more than one workers pool.
* [ ] I have tried reproducing the issue with autoscaling, retries,
  ETA/Countdown & rate limits disabled.
* [x] I have tried reproducing the issue after downgrading
  and/or upgrading Celery and its dependencies.

## Related Issues and Possible Duplicates
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#### Related Issues
* None

#### Possible Duplicates
* None

## Environment & Settings
<!-- Include the contents of celery --version below -->
**Celery version**:4.4.7 and 5.1.2
<!-- Include the output of celery -A proj report below -->
<details>
<summary><b><code>celery report</code> Output:</b></summary>
<p>

```

```

</p>
</details>

# Steps to Reproduce
## Required Dependencies
<!-- Please fill the required dependencies to reproduce this issue -->


* **Minimal Python Version**: N/A or Unknown
* **Minimal Celery Version**: N/A or Unknown
* **Minimal Kombu Version**: N/A or Unknown
* **Minimal Broker Version**: N/A or Unknown
* **Minimal Result Backend Version**: N/A or Unknown
* **Minimal OS and/or Kernel Version**: N/A or Unknown
* **Minimal Broker Client Version**: N/A or Unknown
* **Minimal Result Backend Client Version**: N/A or Unknown

### Python Packages
<!-- Please fill the contents of pip freeze below -->
<details>
<summary><b><code>pip freeze</code> Output:</b></summary>
<p>

```
alabaster==0.7.12
amqp==5.0.6
asgiref==3.3.4
Babel==2.8.0
beautifulsoup4==4.9.3
billiard==116.69.203.115
boto3==1.16.10
botocore==1.19.10
celery==5.1.2
certifi==2020.6.20
chardet==3.0.4
click==7.1.2
click-didyoumean==0.0.3
click-plugins==1.1.1
click-repl==0.2.0
defusedxml==0.6.0
diff-match-patch==20200713
dill==0.3.3
Django==3.2.4
django-amazon-ses==4.0.0
django-appconf==1.0.4
django-bootstrap-breadcrumbs==0.9.2
django-bootstrap-datepicker-plus==3.0.5
django-bootstrap-form==3.4
django-bootstrap4==2.3.1
django-braces==1.14.0
django-chartjs==2.2.1
django-datatables-view==1.19.1
django-debug-toolbar==3.1.1
django-decorator-include==2.1
django-elasticache==1.0.3
django-environ==0.4.5
django-extra-views==0.13.0
django-formtools==2.2
django-imagekit==4.0.2
django-import-export==2.4.0
django-modelsdoc==0.1.11
django-pandas==0.6.4
django-storages==1.10.1
django-summernote==116.69.203.115
django-wkhtmltopdf==3.3.0
docutils==0.14
et-xmlfile==1.0.1
factory-boy==3.1.0
Faker==4.14.0
flower==0.9.5
humanize==3.1.0
idna==2.10
imagesize==1.2.0
jaconv==0.2.4
jdcal==1.4.1
Jinja2==2.11.2
jmespath==0.10.0
klepto==0.2.0
kombu==5.1.0
MarkupPy==1.14
MarkupSafe==1.1.1
numpy==1.18.4
odfpy==1.4.1
openpyxl==3.0.5
packaging==20.4
pandas==1.2.3
pilkit==2.0
Pillow==8.0.1
pox==0.2.9
prometheus-client==0.8.0
prompt-toolkit==3.0.19
psycopg2-binary==2.8.6
pycurl==116.69.203.115
Pygments==2.7.2
pykakasi==2.0.1
pylibmc==1.6.1
pyparsing==2.4.7
python-dateutil==2.8.1
python-magic==0.4.18
pytz==2020.4
PyYAML==5.3.1
redis==3.5.3
requests==2.24.0
s3transfer==0.3.3
six==1.15.0
snowballstemmer==2.0.0
soupsieve==2.0.1
Sphinx==3.2.1
sphinxcontrib-applehelp==1.0.2
sphinxcontrib-devhelp==1.0.2
sphinxcontrib-htmlhelp==1.0.3
sphinxcontrib-jsmath==1.0.1
sphinxcontrib-qthelp==1.0.3
sphinxcontrib-serializinghtml==1.1.4
sqlparse==0.4.1
tablib==2.0.0
tenacity==6.2.0
text-unidecode==1.3
tornado==6.1
urllib3==1.25.11
uWSGI==116.69.203.115
uwsgi-tools==1.1.1
vine==5.0.0
voluptuous==0.12.0
wcwidth==0.2.5
xlrd==1.2.0
XlsxWriter==1.3.7
xlwt==1.3.0
```

</p>
</details>

### Other Dependencies
<!--
Please provide system dependencies, configuration files
and other dependency information if applicable
-->
<details>
<p>
</p>
</details>

## Minimally Reproducible Test Case
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<details>
<p>

```python

```

</p>
</details>

# Expected Behavior
<!-- Describe in detail what you expect to happen -->

# Actual Behavior
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In addition, include the Celery daemon logs, the broker logs,
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When 4 to 8 workers start at the same time, the task will stop consuming.
If there are 2 workers, the problem will not occur.
Once the Visibility Timeout has passed, task digestion will resume.
We use a SQS FIFO queue for brokers.
We do not have this problem when using Redis.


 Comments: 
 Comment 0: Hey @marvelph :wave:,
Thank you for opening an issue. We will get back to you as soon as we can.
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 Comment 1: @galCohen88 can  you check
{'source': 'GithubIssues', 'repo_name_with_owner': 'celery/celery', 'issue_id': 941762732, 'repo_stars': 20350.0}