Blender Git Loki

Fix T71825: Custom Animation Player path overrides chosen player

Thanks @mano-wii for providing the patch!

The original code assumed that when `animation_player_preset` was not
`CUSTOM`, the `animation_player` path would be empty. This is a bad
assumption, as it can be quite useful to be able to toggle between a custom
and a built-in player. As such, `animation_player` should not be reset to
an empty string when a non-custom player is chosen.