Fix: Prevent exception being thrown during datetime comparison (#295)

Because publish_date of Erratum is an offset-aware (UTC timezone) datetime
object, when we compare it with datetime.min, we have to make datetime.min
offset-aware as well.

Author: Jazzcort

supervisor/constants.py

@@ -0,0 +1,3 @@
+from datetime import datetime, timezone
+
+DATETIME_MIN_UTC = datetime.min.replace(tzinfo=timezone.utc)

supervisor/errata_utils.py

@@ -13,6 +13,7 @@
 from pydantic import BaseModel
 from requests_gssapi import HTTPSPNEGOAuth
 
+from .constants import DATETIME_MIN_UTC
 from .http_utils import requests_session
 from .supervisor_types import Erratum, FullErratum, ErrataStatus, Comment
 
@@ -341,7 +342,7 @@ def is_previous_erratum_applicable(erratum_version: str, erratum: Erratum):
         if rel_prep:
             latest_erratum = max(
                 rel_prep,
-                key=lambda e: e.publish_date if e.publish_date else datetime.min,
+                key=lambda e: e.publish_date if e.publish_date else DATETIME_MIN_UTC,
             )
             return latest_erratum