Explain where in a anim state machine a recursive transition is detected

[Flynsarmy]

When a recursive transition is detected in AnimationNodeStateMachinePlayback the following warning is presented to the user (I've submitted a PR to improve the wording):

_transition_to_next_recursive: AnimationNodeStateMachinePlayback: path/to/playback aborts the transition by detecting one or more looped transitions in the same frame to prevent to infinity loop. You may need to check the transition settings.
<C++ Source> scene/animation/animation_node_state_machine.cpp:918 @ _transition_to_next_recursive()

State machines can get complicated in some projects so it may be difficult to tell exactly where the issue is. Transitions obviously don't have names, however the nodes they connect to do. It would be nice if the nodes connected to these transitions were named in the warning so we can easily pinpoint the exact problem with our setup.

For example:

_transition_to_next_recursive: AnimationNodeStateMachinePlayback: parameters/basic_movement/playback has detected one or more looped transitions in a single frame and aborted to prevent an infinite loop. You may need to check the transition settings connecting the 'idle' and 'run' nodes.