[3.x] There are no C# code examples in `Using signals`.

[whtsht]

Your Godot version:
v3.5.2

Issue description:
There is no C# code example in GETTING STARTED >> Step by Step >> Using signals.

URL to the documentation page (if already existing):
https://docs.godotengine.org/en/3.5/getting_started/step_by_step/signals.html

[NEKERAFA]

You have a entry with examples of C# signals in the C# features page (Scripting > Programming Languages > C# > C# features):

https://docs.godotengine.org/en/3.5/tutorials/scripting/c_sharp/c_sharp_features.html#c-signals

[AThousandShips]

The 4.x version has dedicated C# code so makes sense to add in the 3.x one as well

[whtsht]

I plan to submit pull requests for changes to versions 3.4, 3.5, and 3.6 according to C# features page. No C# features page was found for other versions.

[skyace65]

Fixed by #7945.