[v9_11] Prevent possible infinite signing loop after retransferring an inline-signed slave using NSEC3 4727. [bug] Retransferring an inline-signed slave using NSEC3 around the time its NSEC3 salt was changed could result in an infinite signing loop. [RT #45080] (cherry picked from commit f665c724e4ec7fb48100e808a08788904ddd74b6)