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.

editor/plugins/texture_region_editor_plugin.cpp

@@ -36,10 +36,6 @@
 #include "editor/editor_scale.h"
 #include "scene/gui/check_box.h"
 
-/**
-	@author Mariano Suligoy
-*/
-
 void draw_margin_line(Control *edit_draw, Vector2 from, Vector2 to) {
 	Vector2 line = (to - from).normalized() * 10;