[MASSMAIL] pgsql: Don't clobber test exit code at cleanup in LDAP/Kerberors tests

Don't clobber test exit code at cleanup in LDAP/Kerberors tests

If the test script die()d before running the first test, the whole test
was interpreted as SKIPped rather than failed. The PostgreSQL::Cluster
module got this right.

Backpatch to all supported versions.

Discussion: https://www.postgresql.org/message-id/fb898a70-3a88-4629-88e9-f2375020061d@iki.fi

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/3d5a9bb8df65ac6446ae5ad769c0adc5f332c164

Modified Files
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src/test/kerberos/t/001_auth.pl | 7 ++++++-
src/test/ldap/t/001_auth.pl     | 5 +++++
2 files changed, 11 insertions(+), 1 deletion(-)