Use return_value instead of side_effect to avoid StopIteration error

When there are two months to iterate over, the Mock raised a StopIteration error
because it only had one side_effect value. A return_value makes more sense for
the goal of the test.

tests/test_report.py

@@ -29,6 +29,7 @@
 from unittest.mock import patch
 
 import faker
+import q
 from dateutil.relativedelta import relativedelta
 from nise.generators.oci.oci_generator import OCI_REPORT_TYPE_TO_COLS
 from nise.generators.ocp.ocp_generator import OCP_REPORT_TYPE_TO_COLS
@@ -1381,7 +1382,7 @@ def test_gcp_create_report_with_dataset_name_no_report_prefix(self):
         self.assertTrue(os.path.isfile(expected_output_file_path))
         os.remove(expected_output_file_path)
 
-    @patch("nise.report.uuid4", side_effect=["nise"])
+    @patch("nise.report.uuid4", return_value="25150e4f-bfe5-406b-aaa9-b19f59875420")
     def test_gcp_create_report_no_report_prefix(self, patch_etag):
         """Test the gcp report creation method."""
         now = datetime.datetime.now().replace(microsecond=0, second=0, minute=0, hour=0)
@@ -1391,7 +1392,7 @@ def test_gcp_create_report_no_report_prefix(self, patch_etag):
         invoice_month = yesterday.strftime("%Y%m")
         scan_start = yesterday.date()
         scan_end = now.date()
-        expected_file_name = f"{invoice_month}_nise_{scan_start}:{scan_end}.csv"
+        expected_file_name = f"{invoice_month}_{patch_etag.return_value}_{scan_start}:{scan_end}.csv"
         expected_output_file_path = "{}/{}".format(os.getcwd(), expected_file_name)
         self.assertTrue(os.path.isfile(expected_output_file_path))
         os.remove(expected_output_file_path)