test: exclude failing test from coverage check

Signed-off-by: Mike Fiedler <[email protected]>

pyramid_openapi3/tests/test_contenttypes.py

@@ -75,7 +75,7 @@ def test_post_json(self) -> None:
     # FIXME: Something deep in request validation isn't happy right now.
     # Might be related: https://github.com/Pylons/pyramid_openapi3/issues/199
     @unittest.expectedFailure
-    def test_post_form(self) -> None:
+    def test_post_form(self) -> None:  # pragma: no cover
         """Post with `application/x-www-form-urlencoded`."""
 
         res = self._testapp().post("/foo", params={"bar": "baz"}, status=200)