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/godot_navigation_server.cpp

@@ -36,10 +36,6 @@
 #include "navigation_mesh_generator.h"
 #endif
 
-/**
-	@author AndreaCatania
-*/
-
 /// Creates a struct for each function and a function that once called creates
 /// an instance of that struct with the submitted parameters.
 /// Then, that struct is stored in an array; the `sync` function consume that array.