## Problem
We have a couple of CI workflows that still run on Debian Bullseye, and
the default Debian version in images is Bullseye as well (we explicitly
set building on Bookworm)
## Summary of changes
- Run `pgbench-pgvector` on Bookworm (fix a couple of packages)
- Run `trigger_bench_on_ec2_machine_in_eu_central_1` on Bookworm
- Change default `DEBIAN_VERSION` in Dockerfiles to Bookworm
- Make `pinned` docker tag an alias to `pinned-bookworm`