Complete removal of `g_edit_by_live_preview`

What does this MR do and why?

Sets removed_by_url and milestone_removed to comply with the procedure for removing a metrics.

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Before	After

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

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

Related to #424606 (closed)