chore: remove '# type: ignore' for new mypy version

mypy 0.920 now understands the type of
'http.client.HTTPConnection.debuglevel' so we remove the
'type: ignore' comment to make mypy pass

gitlab/client.py

@@ -425,7 +425,7 @@ def enable_debug(self) -> None:
         import logging
         from http.client import HTTPConnection  # noqa
 
-        HTTPConnection.debuglevel = 1  # type: ignore
+        HTTPConnection.debuglevel = 1
         logging.basicConfig()
         logging.getLogger().setLevel(logging.DEBUG)
         requests_log = logging.getLogger("requests.packages.urllib3")