[9.18] fix: usr: Fix a bug in allow-query/allow-transfer catalog zone custom properties

The :iscman:`named` process could terminate unexpectedly when
processing a catalog zone with an invalid ``allow-query`` or
``allow-transfer`` custom property (i.e. having a non-APL type)
coexisting with the valid property. This has been fixed.

Closes #5941

Backport of MR !11954

Merge branch 'backport-5941-catz-catz_process_apl-bug-fix-9.18' into 'bind-9.18'

See merge request isc-projects/bind9!11976