pgsql: ci: remove minor version from freebsd image name

ci: remove minor version from freebsd image name

This way .cirrus.yml does not need to be changed just because freebsd releases
a new minor version.

Discussion: /messages/by-id/20220728095704.ryywoaz4dqqrwstc@alap3.anarazel.de
Backpatch: 15-, just like the CI support

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2827f108d136de518f8f1aa7b1bbef0588e0a680

Modified Files
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.cirrus.yml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)