[python] drop xbmc.abortRequested flag

[enen92]

Description

This PR removes the long deprecated (at least since xbmc.Monitor().abortRequested()) was introduced xbmc.abortRequested flag. This method is not documented in the API since the migration to doxygen/codedocs. In fact I suspect some of the errors seen in #17705 are in fact false positives caused by this old mechanism.

@MilhouseVH I'd probably recommend to include this in your builds and wait ~ a week to see if any regression shows.

Motivation and Context

Cleanup, encourage to use the monitor method instead

How Has This Been Tested?

Tested netflix, tubecast, flask-webinterface-demo addon, and kodi aborts correctly

Types of change

• Bug fix (non-breaking change which fixes an issue)
• Clean up (non-breaking change which removes non-working, unmaintained functionality)
• Improvement (non-breaking change which improves existing functionality)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that will cause existing functionality to change)
• Cosmetic change (non-breaking change that doesn't touch code)
• None of the above (please explain below)

Checklist:

• My code follows the Code Guidelines of this project
• My change requires a change to the documentation, either Doxygen or wiki
• I have updated the documentation accordingly
• I have read the Contributing document
• I have added tests to cover my change
• All new and existing tests passed

[MilhouseVH]

I can see we're going to need to make changes to the LibreELEC Settings add-on once this PR is added, I'll try and make those changes today and then begin testing this, so hopefully in #0430.

[phunkyfish]

Nice

[phunkyfish]

@MilhouseVH Can this go in?

[MilhouseVH]

@MilhouseVH Can this go in?

I think so, yes.