Skip HLS on trivial changes

[palas]

Changelog

- description: |
    Skip HLS checks on trivial changes
  type:
  - maintenance    # not directly related to the code

Context

Doing releases doesn't affect whether HLS works or not. For that reason, we want to skip the check when it doesn't make sense. This PR introduces an exception for when only markdown is changed and for when only the version in a cabal file is changed.

How to trust this PR

It is the same as in the CLI PR: IntersectMBO/cardano-cli#1132

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated. See Running tests for more details
• Self-reviewed the diff