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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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/be0fa5ba003ce1fb955211bead796ae97afbd2a4

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