Override active prune threshold to 1000 years in upgrade tests

We expect to find these entries, but they were being prune and all the
tests broke 60 days after the data was generated.  Bump the threshold to
~1000 years so that they don't get prune.

Author: jagerman

contrib/upgrade-tests/common.sh

@@ -23,6 +23,7 @@ export PYTHONPATH=.
 rm -rf rooms database.db files key_x25519 x25519_{public,private}_key.pem
 
 echo -e "[log]\nlevel = DEBUG" >sogs.ini
+echo -e "[rooms]\nactive_prune_threshold = 365000" >>sogs.ini
 if [ -n "$SOGS_PGSQL" ]; then
     echo -e "[db]\nurl = $SOGS_PGSQL" >>sogs.ini
     for table in rooms users messages message_history pinned_messages files room_users \