fix: escape single quote env var for docker executor

[ANGkeith]

Fixes the error for the following gitlab-ci.yml

docker-executor variables with ':
  image: alpine
  script:
    - echo $CI_JOB_NAME

docker-executor services variables with ':
  services:
    - nginx
  image: alpine
  script:
    - echo $CI_JOB_NAME

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

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