Remove bulk_stick for safety net project_authorization refresh

What does this MR do and why?

Remove bulk_stick for safety net project_authorization refresh

• bulk_stick writes one Redis key per user ID, so the cost scales with the user count and group-wide refreshes pass thousands of IDs.
• The entries expire after 30 seconds while the LOW_PRIORITY refreshes are scheduled to run an 1 hour later, so nothing reads them. Similar case for MEDIUM_PRIORITY.
• Hence, only do this when the job is HIGH_PRIORITY whose target duration is 10 sec.

References

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