<!--Thanks for contributing to GOV.UK Notify. Using this template to write your pull request message will help get it merged as soon as possible. -->

## What problem does the pull request solve?
<!--- Describe why you’re making this change -->

## Checklist

<!--- All of the following are normally needed. Don’t worry if you haven’t done them or don’t know how – someone from the Notify team will be able to help. -->
- [x] I’ve used the pull request template
- [ ] I’ve written unit tests for these changes
- [ ] I’ve update the documentation in
  - `README.md`
  - `CHANGELOG.md`
- [ ] I’ve bumped the version number in
  - `notifications_python_client/__init__.py`
  - `notifications_python_client/test_base_api_client.py`, function `test_user_agent_is_set`
- [ ] I've added new environment variables to
  - `notifications-python-client/scripts/generate_docker_env.sh`
  - `notifications-python-client/tox.ini`
  - `CONTRIBUTING.md`

<!--Thanks for contributing to GOV.UK Notify. Using this template to write your pull request message will help get it merged as soon as possible. -->

## What problem does the pull request solve?
<!--- Describe why you’re making this change -->

## Checklist

<!--- All of the following are normally needed. Don’t worry if you haven’t done them or don’t know how – someone from the Notify team will be able to help. -->
- [x] I’ve used the pull request template
- [ ] I’ve written unit tests for these changes
- [ ] I’ve update the documentation in
  - [ ] `README.md`
  - [ ] `CHANGELOG.md`
- [ ] I’ve bumped the version number in
  - [ ] `notifications_python_client/__init__.py`
  - [ ] `notifications_python_client/test_base_api_client.py`, function `test_user_agent_is_set`
- [ ] I've added new environment variables to
  - [ ] `notifications-python-client/scripts/generate_docker_env.sh`
  - [ ] `notifications-python-client/tox.ini`
  - [ ] `CONTRIBUTING.md`

Add separate checkboxes for all the subcategories
Add separate checkboxes for all the subcategories

so it's obvious that you might want to always add changelog