refactor: do not guess if changelog format is provided, make function private

[bearomorphism]

Description

Checklist

• I have read the contributing guidelines

Code Changes

• Add test cases to all the changes you introduce
• Run poetry all locally to ensure this change passes linter check and tests
• Manually test the changes:
  • Verify the feature/bug fix works as expected in real-world scenarios
  • Test edge cases and error conditions
  • Ensure backward compatibility is maintained
  • Document any manual testing steps performed
• Update the documentation for the changes

Documentation Changes

• Run poetry doc locally to ensure the documentation pages renders correctly
  • Check if there are any broken links in the documentation

When running poetry doc, any broken internal documentation links will be reported in the console output like this:

INFO    -  Doc file 'config.md' contains a link 'commands/bump.md#-post_bump_hooks', but the doc 'commands/bump.md' does not contain an anchor '#-post_bump_hooks'.

Expected Behavior

Steps to Test This Pull Request

Additional Context

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.87%. Comparing base (a9cd957) to head (8e4cdcf).
Report is 9 commits behind head on refactors.

Additional details and impacted files

@@            Coverage Diff             @@
##           refactors    #1471   +/-   ##
==========================================
  Coverage      97.87%   97.87%           
==========================================
  Files             57       57           
  Lines           2677     2678    +1     
==========================================
+ Hits            2620     2621    +1     
  Misses            57       57           

Flag	Coverage Δ
unittests	97.87% <100.00%> (+<0.01%)	⬆️

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[Lee-W]

mostly good, left some nitpicks

[Lee-W]

we probably should make the commit message itself easy to read instead of the github pr title as we're not squashing commits

[Lee-W]

mostly good, but will need your help to resolve conflict and reword commit message

[bearomorphism]

rebased and reworded