Fix outdated keywords autocompletion

modules/gdscript/gdscript_editor.cpp

@@ -1205,8 +1205,8 @@ static void _find_identifiers(const GDScriptParser::CompletionContext &p_context
 	_find_built_in_variants(r_result);
 
 	static const char *_keywords[] = {
-		"false", "PI", "TAU", "INF", "NAN", "self", "true", "breakpoint", "tool", "super",
-		"break", "continue", "pass", "return",
+		"true", "false", "PI", "TAU", "INF", "NAN", "null", "self", "super",
+		"break", "breakpoint", "continue", "pass", "return",
 		nullptr
 	};
 
@@ -1218,7 +1218,7 @@ static void _find_identifiers(const GDScriptParser::CompletionContext &p_context
 	}
 
 	static const char *_keywords_with_space[] = {
-		"and", "in", "not", "or", "as", "class", "extends", "is", "func", "signal", "await",
+		"and", "not", "or", "in", "as", "class", "class_name", "extends", "is", "func", "signal", "await",
 		"const", "enum", "static", "var", "if", "elif", "else", "for", "match", "while",
 		nullptr
 	};