test: add tests for duplicate prevention (fixes #2952)

[kamal2730]

Add tests for PR #2951 - duplicate entries fix in controller exported interfaces. This adds tests for both reference and state interfaces to ensure that calling make_controller_reference_interfaces_available() and make_controller_exported_state_interfaces_available() multiple times does not create duplicate entries.

• Extended managing_controllers_reference_interfaces with duplicate prevention test
• Added new managing_controllers_state_interfaces test with duplicate prevention
• Both tests verify no duplicates are created when making interfaces available multiple times (simulating multiple activate calls) Fixes: Add tests for the duplicate entries in the controller exported interfaces #2952
  See-also: Fix the duplicate entries in the controller exported interfaces #2951

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