title: /bin/bash: line 89: docker: command not found GITLAB CI/CD ISSUE
body: <p>I am trying to push my code on Gitlab using Gitlab CI/CD but it constantly fails on the push stage giving me the below error. 
  Any ideas as to what's causing this?</p>
  
  <p>Issue taken from the push stage:</p>
  
  <pre><code>1 Running with gitlab-runner 12.6.0-rc1 (ec299e72)
  2   on docker-auto-scale 72989761
  3
  Using Docker executor with image ruby:2.5 ...
  00:36
  4 Pulling docker image ruby:2.5 ...
  5 Using docker image sha256:54cb86b0bcdc353e103e9dd1bff69fcd01e3235420ed17cbf5efac22010b373e for ruby:2.5 ...
  7
  Running on runner-72989761-project-16138356-concurrent-0 via runner-72989761-srm-1578059087-b5d7ed4b...
  00:05
  9
  $ eval "$CI_PRE_CLONE_SCRIPT"
  00:01
  10 Fetching changes with git depth set to 50...
  11 Initialized empty Git repository
  12 Created fresh repository.
  14  * [new ref]         refs/pipelines/106842100 -&gt; refs/pipelines/106842100
  15  * [new branch]      master                   -&gt; origin/master
  16 Checking out 54a35cd8 as master...
  17 Skipping Git submodules setup
  21
  $ docker login -u "gitlab-ci-token" -p "$CI_BUILD_TOKEN" "$CI_REGISTRY"
  00:01
  22 /bin/bash: line 89: docker: command not found
  26 ERROR: Job failed: exit code 1
  </code></pre>