Description of problem:

Builder image detection fails for Gitlab & Bitbucket repositories where the default branch is not master.

Both Gitlab and Bitbucket are moving away from using master as the default repository branch according to these sources:
https://about.gitlab.com/blog/2021/03/10/new-git-default-branch-name/
https://bitbucket.org/blog/moving-away-from-master-as-the-default-name-for-branches-in-git

ODC-5285 handled this issue for GitHub.

Prerequisites (if any, like setup, operators/versions):

None

Steps to Reproduce

1. Navigate to Add > Import from git
2. Enter a Gitlab or Bitbucket repository whose default branch is not master, ex. https://bitbucket.org/rottencandy/golang-ex or https://gitlab.com/rottencandy/s2i-dotnetcore-ex

Actual results:

Builder image detection fails

Expected results:

Builder image is detected

Reproducibility (Always/Intermittent/Only Once):

Always