Permissions: fix media showing without permission

In the case of the VideoGridFragment, canReadVideos will always return
true below API 33, showing media if there were media indexed before
revoking file permissions.

On android 11 an 12 (API 30/31/32) when media permission only,
isExternalStorageManager will return false, but checking for
READ_EXTERNAL_STORAGE will return true.

On Android API 33+, if given only audio or video permission,
READ_EXTERNAL_STORAGE will also return true meaning that the check must
be restrained to API 30/31/32,

Furthermore, for API 30/31/32, isExternalStorageManager also needs to be
checked for when the app has full access.

Fixes #3129