Remove spaces in `SubResource()/ExtResource/Resource()` in text resources

These spaces are not needed for the file to be successfully parsed.

Other types such as Vector3 are no longer serialized with spaces
after the opening parenthesis and before the closing parenthesis,
so this is also more consistent.

scene/resources/resource_format_text.cpp

@@ -1564,17 +1564,17 @@ String ResourceFormatSaverTextInstance::_write_resources(void *ud, const Ref<Res
 
 String ResourceFormatSaverTextInstance::_write_resource(const Ref<Resource> &res) {
 	if (external_resources.has(res)) {
-		return "ExtResource( \"" + external_resources[res] + "\" )";
+		return "ExtResource(\"" + external_resources[res] + "\")";
 	} else {
 		if (internal_resources.has(res)) {
-			return "SubResource( \"" + internal_resources[res] + "\" )";
+			return "SubResource(\"" + internal_resources[res] + "\")";
 		} else if (!res->is_built_in()) {
 			if (res->get_path() == local_path) { //circular reference attempt
 				return "null";
 			}
 			//external resource
 			String path = relative_paths ? local_path.path_to_file(res->get_path()) : res->get_path();
-			return "Resource( \"" + path + "\" )";
+			return "Resource(\"" + path + "\")";
 		} else {
 			ERR_FAIL_V_MSG("null", "Resource was not pre cached for the resource section, bug?");
 			//internal resource