Revert "Return error when no ResourceFormatLoader found."

This reverts commit 6df3621b472f7033de9d8391a2057a64aa5a42d6.

Fixes #97153.

core/io/resource_loader.cpp

@@ -303,10 +303,6 @@ Ref<Resource> ResourceLoader::_load(const String &p_path, const String &p_origin
 		return res;
 	}
 
-	if (r_error) {
-		*r_error = ERR_FILE_UNRECOGNIZED;
-	}
-
 	ERR_FAIL_COND_V_MSG(found, Ref<Resource>(),
 			vformat("Failed loading resource: %s. Make sure resources have been imported by opening the project in the editor at least once.", p_path));