Improve logging of test for panel destruction

[feerrenrut]

Link to issue number:

None

Summary of the issue:

While looking into #12220, I noticed a lot of logging noise for the tests for destruction of settings panels.

A little investigation showed that the same settings dialogs was being marked as destroyed previously because the evt.skip()
was not called.
Calling skip is not appropriate, but it is also not necessary to log that the dialog which is already marked as destoyed, will be again.

Description of how this pull request fixes the issue:

Use an enum for destroyed state, this logs better.
Only log if the dialog is not already marked as destoyed.
Improve what is logged so that the dialog is actually identifiable.

Example log message after PR:

Input: kb(desktop):escape
DEBUG - gui.settingsDialogs.SettingsDialog._setInstanceDestroyedState (18:46:00.444) - MainThread (15748):
Setting state to destroyed for instance: Input Gestures - InputGesturesDialog - <gui.inputGestures.InputGesturesDialog object at 0x1AB17DA8>
Current _instances ['NVDA Settings - CREATED', 'Input Gestures - CREATED']
IO - speech.speak (18:46:00.517) - MainThread (15748):
Speaking [LangChangeCommand ('en'), 'NVDA Settings: General (normal configuration)', 'dialog', CancellableSpeech (still valid)]
IO - speech.speak (18:46:00.519) - MainThread (15748):
Speaking [LangChangeCommand ('en'), 'Categories:', 'list', CancellableSpeech (still valid)]
IO - speech.speak (18:46:00.521) - MainThread (15748):
Speaking [LangChangeCommand ('en'), 'General', '1 of 13', CancellableSpeech (still valid)]
IO - inputCore.InputManager.executeGesture (18:46:00.802) - winInputHook (12364):
Input: kb(desktop):escape
DEBUG - gui.settingsDialogs.SettingsDialog._setInstanceDestroyedState (18:46:00.804) - MainThread (15748):
Setting state to destroyed for instance: NVDA Settings - NVDASettingsDialog - <gui.settingsDialogs.NVDASettingsDialog object at 0x1A8F8100>
Current _instances ['NVDA Settings - CREATED']

Testing strategy:

Ran locally with the NVDA settings dialog, checked log.

Known issues with pull request:

None

Change log entry:

None, these were internal constants, meant for debugging purposes only.

Code Review Checklist:

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• Unit tests.
• System (end to end) tests.
• Manual tests.
• User Documentation.
• Change log entry.
• Context sensitive help for GUI changes.