pgsql: Fix missing "use Test::More" in Kerberos.pm.

Fix missing "use Test::More" in Kerberos.pm.

Apparently the only Test::More function this script uses is
BAIL_OUT, so this omission just results in the wrong error
output appearing in the cases where it bails out.

Seems to have been an oversight in commit 9f899562d which
split Kerberos.pm out of another script.

Author: Maxim Orlov <orlovmg(at)gmail(dot)com>
Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/CACG=ezY1Dp-S94b78nN0ZuaBGGcMUB6_nF-VyYUwPt1ArFqmGA@mail.gmail.com
Backpatch-through: 17

Branch
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REL_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/71ee96e9f95806f9f6e2c805496c0dcf25b3946a

Modified Files
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src/test/perl/PostgreSQL/Test/Kerberos.pm | 1 +
1 file changed, 1 insertion(+)