test: Upgrade "freezegun" to 1.1.0 (#23243)

requirements-dev.txt

@@ -1,6 +1,6 @@
 docker>=3.7.0,<3.8.0
 exam>=0.5.1
-freezegun==0.3.11
+freezegun==1.1.0
 honcho>=1.0.0,<1.1.0
 openapi-core @ https://github.com/getsentry/openapi-core/archive/master.zip#egg=openapi-core
 pytest==4.6.5