Bump version to 3.2.3-stable

A fairly big new release fixing many issues all around the engine,
as well as bringing many improvements for C# users.

Thanks to all contributors! <3

version.py

@@ -3,7 +3,7 @@ name = "Godot Engine"
 major = 3
 minor = 2
 patch = 3
-status = "rc"
+status = "stable"
 module_config = ""
 year = 2020
 website = "https://godotengine.org"