Configurable permissions for triggering the Test Repository Integrity Checker

The "Fix Integrity" operation is resource-intensive and can slow down Jira. Currently, any user with project edit permissions can trigger it. This is risky on large instances, as regular users may accidentally impact system performance.

We should create a new setting in the Xray configuration to allow only Administrators to fix integrity issues.

Non-Admins can see the warning but cannot run the fix.