pgsql: ci: Upgrade to Debian Bookworm

ci: Upgrade to Debian Bookworm

Bullseye is getting long in the tooth, upgrade to the current stable version.

Backpatch to all versions with CI support, we don't want to generate CI images
for multiple Debian versions.

Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/CAN55FZ0fY5EFHXLKCO_%3Dp4pwFmHRoVom_qSE_7B48gpchfAqzw%40mail.gmail.com
Backpatch: 15-, where CI was added

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c8a6ec206a9940551f3de80a6e5a10377056781c

Modified Files
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.cirrus.tasks.yml | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)