[MSD benchmark] Date override fixes

[khaliqgant]

MSD benchmark PR recreated from Martian Code Review Bench.

Source PR: calcom#8330
Dataset: cal_dot_com
Original title: Date override fixes

What does this PR do?

This PR fixes that date overrides of fixed hosts are taken into account for round-robin events. This prevents round-robin events being booked where the fixed hosts are unavailable.

This PR also fixes that date overrides didn't adjust to different timezones. If the organizer has a date override from 10-11 UTC it always showed the slots from 10-11 open no matter what timezone the attendee has.

Fixes calcom#8207
Fixes calcom#8329

Fixes: calcom#8273

Environment: Staging(main branch) / Production

Type of change

• Bug fix (non-breaking change which fixes an issue)

How should this be tested?

Date overrides for fixed hosts (round-robin):

• Create a round-robin event with one fixed host and host round-robin host
• Create a date override for fixed host (round-robin host should also be available at that time)
• Check available slots of event on the day of the date override, it should only show the slots where fixed host is available
• Test that with different time zones on booking page and on the availabilities of fixed and round-robin host

Date override timezones issue:

• Create a date override
• Go to the booking page of a personal event
• Change the timezone to a different one that the availability with the date override is
• See the available slots of the day with the date override change accordingly
• Also test with different timezones here