perl tap: Use croak instead of die in our helper modules

perl tap: Use croak instead of die in our helper modules

Replace die with croak throughout Cluster.pm and Utils.pm (except in
INIT blocks and signal handlers, where die is correct) so that error
messages report the test script's line number rather than the helper
module's.

Add @CARP_NOT in Utils.pm listing PostgreSQL::Test::Cluster, so that
when a Utils function is called through a Cluster.pm wrapper, croak
skips both packages and reports the actual test-script caller.

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Zsolt Parragi <zsolt.parragi@percona.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/DFYFWM053WHS.10K8ZPJ605UFK@jeltef.nl