revert forked redis lib change (#3600) (#3609)

# What this PR does

Reverts #3600 (related to
grafana/oncall-private#2406)

engine/requirements.txt

@@ -5,10 +5,7 @@ whitenoise==5.3.0
 twilio~=6.37.0
 phonenumbers==8.10.0
 celery[amqp,redis]==5.3.1
-# NOTE: temporarily installing a forked version of redis-py which adds some more debug logging
-# in an effort to fix https://github.com/grafana/oncall-private/issues/2406
-# revert this change once done debugging
-git+https://github.com/grafana/redis-py@0c88554
+redis==5.0.1
 humanize==0.5.1
 uwsgi==2.0.21
 django-cors-headers==3.7.0