Disable aspect ratio settings floating button when already in app menu

If overridesShowAppHandle, the aspect ratio button is already present in
the app menu when needed, and therefore the old floating button is not
necessary.

Bug: 377689543
Test: Manual, enabling the show app handle override disables the
floating button
Flag: com.android.window.flags.show_app_handle_large_screens

Change-Id: Ied8d32f2613b5acde36f6e17fb5f18982243f6d3