Add identity test for EnumIvoryTower single

[ZachT01]

This pull request adds a new JUnit test verifying that EnumIvoryTower.INSTANCE
returns the same instance on repeated access. This improves test coverage for
the Enum-based singleton implementation.

[github-actions]

PR Summary

Added a new JUnit test to verify that EnumIvoryTower.INSTANCE returns the same instance on repeated access, reinforcing the Enum-based singleton behavior. The test imports assertSame and runs alongside the existing reflection-based test to ensure the constructor cannot be invoked reflectively.

Changes

File	Summary
singleton/src/test/java/com/iluwatar/singleton/EnumIvoryTowerTest.java	Added an identity test verifying singleton nature of EnumIvoryTower.INSTANCE by asserting reference equality; updated imports to include assertSame; preserves existing reflection test.

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autogenerated by presubmit.ai

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• 54d96a8: Add identity test for EnumIvoryTower single

Files Processed (1)

• singleton/src/test/java/com/iluwatar/singleton/EnumIvoryTowerTest.java (2 hunks)

Actionable Comments (0)

Skipped Comments (2)

• singleton/src/test/java/com/iluwatar/singleton/EnumIvoryTowerTest.java [29-29]

  best_practice: "Import for new assertion"

• singleton/src/test/java/com/iluwatar/singleton/EnumIvoryTowerTest.java [51-56]

  enhancement: "Verify enum singleton identity test"