Create custom TimeRangeSearchToken

What does this MR do and why?

Add custom date range filter to the tracing filter bar, and enable the zoomer on the scatter chart, to allow the user to focus the chart on a more precise time range.

The approach used to add the date picker has been reviewed and discussed here: Draft: DatePicker Filter Token - investigation (gitlab-ui!3837 - closed) In short, the token is re-activated if the selected value is custom-date, and the date-picker shown so that the value can be set to a date range.

Closes Search traces by custom time range (gitlab-org/opstrace/opstrace#2380 - closed)

Screenshots or screen recordings

Screen_Recording_2023-12-15_at_10.39.15

How to set up and validate locally

• Enable observability_tracing feature flag
• Apply patch to load mocks
• Go to https://local.gitlab.com:3443/flightjs/Flight/-/tracing
• Play around with the date range filtre (note that the mocked data might not match the filters )

MR acceptance checklist

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

• I have evaluated the MR acceptance checklist for this MR.