Fix compliance report merged at dates for all timezones

What does this MR do and why?

This MR fixes the merged at date usages on the compliance report for all time zones. Previously, any UTC-* timezone caused the selected filtering date to be converted to the day before and was made even more confusing the table make use of relative dates with absolute tooltips.

So this MR does the following:

  • Forces the filters to use UTC+0 for all dates
  • Changes the report tables merged at dates to be absolute UTC+0 rather than relative and removes the tooltip
Before UTC-10 (had to select a day ahead to make it work) After UTC-10
Screenshot_2022-08-03_at_10.41.53 Screenshot_2022-08-03_at_06.38.16

How to set up and validate locally

  1. Visit a groups compliance dashboard e.g. http://gdk.test:3000/groups/gitlab-org/-/security/compliance_dashboard.
  2. Change the To date filter to the same date as a compliance violation.
  3. Confirm that the compliance violation is still shown.
  4. If you aren't in a UTC-* timezone, change your devices timezone to one (for example US/Pacific).
  5. Reconfirm that the compliance violation is still shown when the filter is set to the same date.
  6. Confirm in all cases that the correct merged at dates are shown on the violations list.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

Related to #367675 (closed)

Edited by Robert Hunt