Replace `Support Interest::` labels with `Support Priority::` labels on Managing Product Issues page

Why is this change being made?

Based on decisions made today in a meeting between Fulfillment -> Provision and L&R Support, the labeling scheme for our list of prioritized issues, which is documented on the Managing Product Issues page, needs to change. This MR makes those changes.

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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