VSA - Support full UTC timestamp for date range filters

Problem to solve

This issue covers the frontend work to support a full UTC timestamp in the VSA created_after and created_before date range filters. This follows from the work in VSA - Expose timestamp in VSA created_after an... (#374297)

Proposal

• FE converts the timestamp to the user's timezone, populates the date selector.
• FE invokes the API calls to load the data using the same UTC timestamps.
• FE receives data (issue list or anything with timestamp) and converts the timestamps to the user's timezone.

Intended users

Feature Usage Metrics

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