The bloom render pass has been deprecated in Blender 4.2. It was still
visible in the UI in the shading popover and available in the python API.
This PR removes the UI option and deprecated the parts of the python API.
Current add-ons that use this API should still be able to use the API, but
it would not do anything. Add-ons are encourage to remove these calls.
The flags are not cleaned up so they should still work when switching back
to previous Blender versions.
Release notes have been updated to include these changes.
Pull Request: https://projects.blender.org/blender/blender/pulls/123059
0f5ddd5807