pgsql: ci: Move to per-job naming for containers

ci: Move to per-job naming for containers

Previously we only had two types of containers, "ci" for everything but
the CompilerWarnings job and ci_docs that had the tools necessary to
build the docs as part of CompilerWarnings. But that was unnecessarily
heavy for several of the jobs. As the pull time is a noticeable
performance factor, that's not great.

Instead use containers that are named by their job. Today some of those
are the same, but after this change we can optimize the containers for
their jobs without a problem.

It probably would make sense to allow over-riding CONTAINER_REPO on a
per-repo/org basis, but that seems better done as a separate change.

This commit is backpatched to 19 to keep CI between master and 19 the
same. Soon we'll backpatch CI support to regain coverage with lost with
cirrus-ci's shutdown.

Author: Andres Freund <andres(at)anarazel(dot)de>
Co-authored-by: Nazir Bilal Yavuz <byavuz81(at)gmail(dot)com>
Discussion: https://postgr.es/m/a2ejn7lfqolutzz7kozalbhy3bixdrujb4buc3pgbtlk4am2ba@wbv6v7riia33
Discussion: https://postgr.es/m/CAN55FZ1BcWBsWgCCk2GQkYN6tzDxCw2hVK2m3qeiwaNXUnjLVg@mail.gmail.com
Backpatch-through: 19

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/29fffc1a66456babfba35771b9ec644e3137164a

Modified Files
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.github/workflows/pg-ci.yml | 33 ++++++++++++++++++++++-----------
1 file changed, 22 insertions(+), 11 deletions(-)