Refactored reports to use pregenerated docs instead (#2831)

* Refactored reports to use pregenerated docs instead

* Fixed e2e test

* Fixed anothr bug

* Cleanup

* Fixed timezone conversion

* Updated ref files

* Updated reference files, refreshed ui/ux for report generation. Buttons toggle on and off based on if report exists

* Fixed linting errors, removed pytz

* Fixed test failure

* e2e test fix

* Speeding up unit tests

* Removed python time library that was causing performance issues with unit tests

* Updated poetry lock

* Unit test improvements

* Made change that ken reccomended

notifications_utils/letter_timings.py

@@ -1,7 +1,6 @@
 from collections import namedtuple
 from datetime import datetime, time, timedelta
-
-import pytz
+from zoneinfo import ZoneInfo
 
 from notifications_utils.countries.data import Postage
 from notifications_utils.timezones import utc_string_to_aware_gmt_datetime
@@ -19,9 +18,9 @@ CANCELLABLE_JOB_LETTER_STATUSES = [
 
 def set_gmt_hour(day, hour):
     return (
-        day.astimezone(pytz.timezone("Europe/London"))
+        day.astimezone(ZoneInfo("Europe/London"))
         .replace(hour=hour, minute=0)
-        .astimezone(pytz.utc)
+        .astimezone(ZoneInfo("UTC"))
     )
 
 
@@ -91,8 +90,8 @@ def get_letter_timings(upload_time, postage):
     printed_by = set_gmt_hour(print_day, hour=15)
     now = (
         datetime.utcnow()
-        .replace(tzinfo=pytz.utc)
-        .astimezone(pytz.timezone("Europe/London"))
+        .replace(tzinfo=ZoneInfo("UTC"))
+        .astimezone(ZoneInfo("Europe/London"))
     )
 
     return LetterTimings(