Docs: Add missing descriptions to @return tags

[huzaifaalmesbah]

Description

This PR addresses missing descriptions in @return tags within the includes directory, ensuring compliance with documentation standards.

Changes

• Added missing descriptions to @return tags in includes/Experiments/Example_Experiment/Example_Experiment.php.

[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 50.80%. Comparing base (1351969) to head (965498c).
⚠️ Report is 5 commits behind head on develop.

Additional details and impacted files

@@            Coverage Diff             @@
##             develop     #210   +/-   ##
==========================================
  Coverage      50.80%   50.80%           
  Complexity       375      375           
==========================================
  Files             27       27           
  Lines           1978     1978           
==========================================
  Hits            1005     1005           
  Misses           973      973           

Flag	Coverage Δ
unit	50.80% <ø> (ø)

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