Update contributing guide to include Maven version requirement

[programbeginnerTW]

What I did

• Added Maven 3.9.6 requirement to the contributing guide.

Testing done

• Verified the documentation build process to ensure no formatting issues.
• Manually reviewed the contributing guide for clarity and completeness.

Submitter checklist

• The pull request is from a feature branch and not the main branch.
• The pull request title represents the desired changelog entry.
• The documentation update is clearly described.
• Linked to the relevant issue in GitHub.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 72.04%. Comparing base (41f98d9) to head (9c0cde7).
Report is 9 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #514      +/-   ##
============================================
+ Coverage     71.73%   72.04%   +0.30%     
- Complexity      222      235      +13     
============================================
  Files            17       18       +1     
  Lines          1033     1073      +40     
  Branches        148      149       +1     
============================================
+ Hits            741      773      +32     
- Misses          201      207       +6     
- Partials         91       93       +2     

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