Accept url as forbidden if HTTP method not supported

tests/frontend/assertions.py

@@ -90,7 +90,7 @@ def assert_url_forbidden(self, url: str, method: str = "HEAD", **kw) -> Response
         resp = self.open(url, method=method, **kw)
         status = resp.status_code
         assert (
-            status == 403
+            status == 403 or status == 405
         ), f"Access to {url} expected to be forbidden, got status {status}"
         return resp