Update to HPAR ticket workflow for Support

Why is this change being made?

Based on this slack discussion, our current High Priority All-Region (HPAR) ticket workflow needs to be further refined to ensure that the tickets are being monitored and responded to across all regions.

In the "All Regions" Ticket Workflow Refinement and Iteration issue, it is discussed that the handover of these tickets is an integral part of the workflow. This MR proposes a handover workflow to assist in a smooth transition of HPAR tickets across regions until they are solved or the priority is lowered.

Author Checklist

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