Improve coverage for core utility classes

[RoiSoleil]

Improved code coverage by adding unit tests for three utility classes in the org.moreunit.core bundle: ArrayUtils, Preconditions, and ExtendedSafeRunner. These tests ensure that the core logic of these utilities is correctly verified.

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PR created automatically by Jules for task 8702093671803069398 started by @RoiSoleil

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[codecov]

Codecov Report

❌ Patch coverage is 74.22680% with 25 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.30%. Comparing base (19d2559) to head (08ee1d4).
⚠️ Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
...test/org/moreunit/core/util/PreconditionsTest.java	59.64%	23 Missing ⚠️
...org/moreunit/core/util/ExtendedSafeRunnerTest.java	91.30%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #239      +/-   ##
============================================
+ Coverage     73.20%   73.30%   +0.10%     
- Complexity     3206     3235      +29     
============================================
  Files           416      420       +4     
  Lines         14339    14435      +96     
  Branches       1266     1266              
============================================
+ Hits          10497    10582      +85     
- Misses         3307     3322      +15     
+ Partials        535      531       -4     

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