Mono: Default to not shipping C# scripts content

Fixes #20053.

modules/mono/csharp_script.cpp

@@ -121,7 +121,7 @@ void CSharpLanguage::init() {
 #ifdef TOOLS_ENABLED
 	EditorNode::add_init_callback(&gdsharp_editor_init_callback);
 
-	GLOBAL_DEF("mono/export/include_scripts_content", true);
+	GLOBAL_DEF("mono/export/include_scripts_content", false);
 #endif
 }