fix(pytest): ignore asyncio.base_events deprecation warnings

This deprecation warning is not fixed in a tagged release yet.
Ignoring it for now; it has nothing to do with user code.

Upstream bug at https://bugs.python.org/issue45097

Signed-off-by: Kevin Morris <kevr@0cost.org>

pytest.ini

+[pytest]
+# Ignore the following DeprecationWarning(s):
+#   - asyncio.base_events
+#       - DeprecationWarning speaking about internal asyncio
+#         using the loop= argument being deprecated starting
+#         with python 3.8, before python 3.10.
+#       - Note: This is a bug in upstream filed at
+#         https://bugs.python.org/issue45097
+filterwarnings =
+    ignore::DeprecationWarning:asyncio.base_events