refactor(bump): cleanup related to update_version_file

[bearomorphism]

Description

Try to address confusing variable names and function names, also reduced the number of function parameters for better readability.

Relate #1580

Better test coverage for update_version_in_file:

• Covered return value
• Covered check_consistency=True
• Covered other encoding values

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 and fix any broken links (internal or external) 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.
⚠️ Please upload report for BASE (v4-9-2@835ccb4). Learn more about missing BASE report.

Additional details and impacted files

@@            Coverage Diff            @@
##             v4-9-2    #1594   +/-   ##
=========================================
  Coverage          ?   98.71%           
=========================================
  Files             ?       60           
  Lines             ?     2654           
  Branches          ?        0           
=========================================
  Hits              ?     2620           
  Misses            ?       34           
  Partials          ?        0           

Flag	Coverage Δ
unittests	98.71% <100.00%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[bearomorphism]

btw the return value is not covered in the unit tests for this function. I'm not sure if it's covered anywhere else.