使用python image和if条件编写了下面的gitlab管道。

.chk-bracket:
  image: "python:3.7"
  before_script:
    - apt update
    - apt install jq -y 
    - pip install awscli
    
  script:
    - echo $CI_COMMIT_MESSAGE
    - |
      if [[ $CI_COMMIT_MESSAGE = *"_test"* ]]; then
        echo "testing"
      fi
  rules:
    - if: $CI_COMMIT_BRANCH =~ /^develop/ && $CI_COMMIT_MESSAGE =~ /.*build_test.*/

后来我们用docker image代替python image进行了重构，if条件开始失败，它没有打印测试，当然我在原来复杂的gitlab管道代码中简化了if条件

.chk-bracket:
  image: "docker:stable"
  before_script:
    - apk update
    - apk add py-pip jq bash
    - pip install awscli
  script:
    - echo $CI_COMMIT_MESSAGE
    - |
      if [[ $CI_COMMIT_MESSAGE = *"_test"* ]]; then
        echo "testing"
      fi
  rules:
    - if: $CI_COMMIT_BRANCH =~ /^develop/ && $CI_COMMIT_MESSAGE =~ /.*build_test.*/

有什么线索说明为什么这种情况在docker图像中不起作用吗？