Issue Summary

In bitbucket cloud pipelines, if a user is not mentioning any image it by default picks the atlassian default image with tag :latest and this image is 5 years old image

Steps to Reproduce

• Create a pipeline image without mentioning any image name OR with image tag as below

  image: atlassian/default-image:latest
  
  pipelines:
    default:
      - parallel:
        - step:
            name: 'Build and Test'
            script:
              - git --version
  

• Check the SHA value of the image used from the pipeline build results

  Images used:
  build : docker.io/atlassian/default-image@sha256:689e2c63e20a48e0a4d31156adcf32b4474dc32b50ab05abe3682b39fb9767a8
  

  This is the same 5 years old SHA with the tag latest, refer to this docker hub page as well

Expected Results

The default image with the "default-image:latest" tag should point to the latest available released version.

Actual Results

Pointing to some 5 years old image docker hub

Workaround

The latest tag atlassian/default-image:latest is currently using version 1 in order to keep compatibility with existing Bitbucket Pipelines builds.

However, we strongly recommend‌ that you select a specific version (4.x) in order to prevent breaking changes from impacting your setup. You can use a specific version by using a version number tag: atlassian/default-image:4. This will install the latest 4.x version that is available.