pgsql: Trial fix for old cross-version upgrades.

Trial fix for old cross-version upgrades.

Per buildfarm and reports, it seems that 9.X to 18 upgrades were
failing after commit 1fd1bd8710 due to an incorrect regex. Loosen the
regex to accommodate older versions.

Reported-by: vignesh C <vignesh21@gmail.com>
Reported-by: Andrew Dunstan <andrew@dunslane.net>
Discussion: https://postgr.es/m/CALDaNm3GUs+U8Nt4S=V5zmb+K8-RfAc03vRENS0teeoq0Lc6Tw@mail.gmail.com
Discussion: https://postgr.es/m/ea4cbbc1-c5a5-43d1-9618-8ff3f2155bfe@dunslane.net

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ab84d0ff806dd791ea9da5f1ca302daf3cf42980

Modified Files
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src/test/perl/PostgreSQL/Test/AdjustUpgrade.pm | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)