Show current time in time format preference labels
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Follow up from https://gitlab.com/gitlab-org/gitlab/-/merge_requests/130789#note_1639301924
### Current
We show static examples of time formats in preferences
### Proposal
Show the user's current time in each option. For example, if it's 2:48PM my time (and my system preferences are set to 12h format), I'd see the following:

issue