Update CI workflow

.github/workflows/ci.yml

@@ -16,5 +16,5 @@ jobs:
           pip install -r requirements.txt -r requirements-dev.txt
       - name: "Run tests"
         run: python -m unittest discover
-        with:
+        env:
           SKIP_PROCESS_DIFF_TEST: true

tests/test_process_diff.py

@@ -74,7 +74,7 @@ class IssueUrlInsertionTest(unittest.TestCase):
     # this test can take a while and, as far as TodoParser is concerned,
     # redundant with the tests of test_todo_parser, so enable the means
     # to skip it if desired
-    @unittest.skipIf(os.getenv('INPUT_SKIP_PROCESS_DIFF_TEST', 'false') == 'true',
+    @unittest.skipIf(os.getenv('SKIP_PROCESS_DIFF_TEST', 'false') == 'true',
                      "Skipping because 'SKIP_PROCESS_DIFF_TEST' is 'true'")
     def test_url_insertion(self):
         self._setUp(['test_new.diff'])