test: improve coverage for util classes

[RoiSoleil]

This PR adds unit tests for Objects and IOUtils in org.moreunit.core.util to improve test coverage.

• Tested classes: Objects, IOUtils
• Added tests for Objects.equal and Objects.hash
• Added tests for IOUtils.closeQuietly handling arrays, multiple elements, and exception paths during closure.

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PR created automatically by Jules for task 7278692114442908833 started by @RoiSoleil

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.79%. Comparing base (e46ea62) to head (9b20ce3).

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #352      +/-   ##
============================================
+ Coverage     79.73%   79.79%   +0.06%     
- Complexity     4048     4062      +14     
============================================
  Files           511      513       +2     
  Lines         17292    17340      +48     
  Branches       1339     1339              
============================================
+ Hits          13788    13837      +49     
+ Misses         2937     2936       -1     
  Partials        567      567              

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