Log Message:
dovecot-pigeonhole: updated to 0.5.9

v0.5.9:
+ Added events for Sieve and ManageSieve, see
  https://doc.dovecot.org/admin_manual/list_of_events/#pigeonhole
+ Pigeonhole: Implement the Sieve "special-use" extension described in
  RFC 8579.
- duplicate: Test only compared the handles which would cause
  different values to be cached as the same duplicate test. Fix to also
  compare the actual hashes.
- imap_sieve_filter: IMAP FILTER Command had various bugs in error
  handling. Errors may have been duplicated for each email, errors
  may have been missing entirely, command tag and ERRORS/WARNINGS
  parameters were swapped.