Change the way the migration determines what the timezone to infer for not-meeting-specific timestamps should be.

 - Legacy-Id: 18823

Author: rjsparks

ietf/utils/migrations/0002_convert_timestamps.py

@@ -24,7 +24,7 @@
 # ----------------------------------------------------------------------
 
 def forward(apps, schema_editor):
-    tzfrom = pytz.timezone(settings.TIME_ZONE)
+    tzfrom = pytz.timezone('PST8PDT')
     tzto   = pytz.utc
     convert(apps, tzfrom, tzto)