Style: Remove inconsistently used @author docstrings

Each file in Godot has had multiple contributors who co-authored it over the
years, and the information of who was the original person to create that file
is not very relevant, especially when used so inconsistently.

`git blame` is a much better way to know who initially authored or later
modified a given chunk of code, and most IDEs now have good integration to
show this information.

modules/navigation/nav_utils.h

@@ -35,10 +35,6 @@
 
 #include <vector>
 
-/**
-	@author AndreaCatania
-*/
-
 class NavRegion;
 
 namespace gd {