UNT0021 falsely flags StateMachineBehaviour messages

[Faulo]

Bug description

UNT0021 (Unity message should be protected) claims the various StateMachineBehaviour messages should be protected, but those methods are declared public by the Unity source code itself and therefor cannot be made protected upon extension.

• Version of analyzers assembly: 4.11.4.0
• Analyzer rule: UNT0021
• Error: CS0507 cannot change access modifiers when overriding inherited member

To Reproduce

Steps or code to reproduce the behavior:

1. Create a script that extends UnityEngine.StateMachineBehaviour.
2. Override the public OnStateEnter message.
3. See the (impossible) suggestion to turn it protected.

Expected behavior

UNT0021 should never flag messages that are declared public in the Unity source code.

Screenshots

At least these messages are affected:

[sailro]

Indeed we should not warn for overridden messages, given they will use the scope of the member definition. This rule is only interesting for regular messages.

I'm going to fix this.

Thanks!