When eye gaze is not enabled, we get errors when action map contains eye gaze interaction

[BastiaanOlij]

The action map logic in Godot is build in such a way that all interactions can be added to the action map provided the entries appear in the meta data. The action map logic will then filter out unsupported bindings on load.

The problem with our eye gaze extension is that when it's not enabled, we don't instantiate the class at all, leading to errors when we're trying to load action maps that contain the eye gaze interaction:

modules/openxr/editor/openxr_interaction_profile_editor.cpp:260 - Parameter "profile_def" is null.

In situations where extensions introduce meta data for the action map system, we should probably make an exception and instance the class, but skip trying to activate the extension.

[BastiaanOlij]

Should be resolved by godotengine/godot#88754