Merge #1345 (update pip to 23.0.1)

Author: martey

requirements/production.txt

@@ -12,7 +12,7 @@ django-timezone-field==4.2.3
 easy-thumbnails==2.8.3
 gunicorn==20.1.0
 pinax-eventlog==5.1.1
-pip==22.3.1
+pip==23.0.1
 -e git+https://github.com/pretalx/pretalx@9b0934c0cef6ec022608ff19ab15176528dac345#egg=pretalx[redis]&subdirectory=src
 psycopg2==2.9.5
 pytz==2022.6