Fix warning spam when using `--help` or `--version` command line argument

When a project setting is not found, a warning message is printed.
This moves the default value declaration so it can be found when
the `--help` or `--version` command line arguments are used.

(cherry picked from commit 5cd37de1254011fb5a4d675d9a5894382c0d9b4c)

main/main.cpp

@@ -369,6 +369,11 @@ Error Main::setup(const char *execpath, int argc, char *argv[], bool p_second_ph
 	ClassDB::register_class<Performance>();
 	engine->add_singleton(Engine::Singleton("Performance", performance));
 
+	// Only flush stdout in debug builds by default, as spamming `print()` will
+	// decrease performance if this is enabled.
+	GLOBAL_DEF("application/run/flush_stdout_on_print", false);
+	GLOBAL_DEF("application/run/flush_stdout_on_print.debug", true);
+
 	GLOBAL_DEF("debug/settings/crash_handler/message", String("Please include this when reporting the bug on https://github.com/godotengine/godot/issues"));
 
 	MAIN_PRINT("Main: Parse CMDLine");
@@ -971,11 +976,6 @@ Error Main::setup(const char *execpath, int argc, char *argv[], bool p_second_ph
 	}
 #endif
 
-	// Only flush stdout in debug builds by default, as spamming `print()` will
-	// decrease performance if this is enabled.
-	GLOBAL_DEF("application/run/flush_stdout_on_print", false);
-	GLOBAL_DEF("application/run/flush_stdout_on_print.debug", true);
-
 	GLOBAL_DEF("logging/file_logging/enable_file_logging", false);
 	// Only file logging by default on desktop platforms as logs can't be
 	// accessed easily on mobile/Web platforms (if at all).