fix flux submission test

tests/test_cache_executor_pysqa_flux.py

@@ -33,7 +33,7 @@ def mpi_funct(i):
 class TestCacheExecutorPysqa(unittest.TestCase):
     def test_executor(self):
         with Executor(
-            backend="pysqa_flux",
+            backend="flux_submission",
             resource_dict={"cores": 2, "cwd": "cache"},
             block_allocation=False,
             cache_directory="cache",