feat(ci)!: switch to rpmbuild

[madonuko]

Rationale

As proven in the experimental Terra EL10 branch (el10), switching to -rrpmbuild has significantly decreased time required to build packages, speeding up CI.

Since frawhide is our other "half-pseudo-experimental" branch, we will start deploying this change to this branch first, then backporting this to older branches.

This supposedly does not affect reproducibility because we have been using our own Terra builders inside our mock configs.
Assuming we set up an environment identical to what the mock configs had specified, this should not cause any breaking changes.

However

Some existing anda options, including extra_repos, are not supported under -rrpmbuild.

[raboneko]

💔 All backports failed

Status	Branch	Result
❌	f39	Backport failed because of merge conflicts You might need to backport the following PRs to f39: - feat(ci): fix bugs with update backporting, add weekly mode, remove f39, add el10 (#2610) - fix(ci): try $GITHUB_SHA instead (#1624)
❌	f40	An unhandled error occurred. Please see the logs for details
❌	f41	An unhandled error occurred. Please see the logs for details
❌	el10	Backport failed because of merge conflicts You might need to backport the following PRs to el10: - fix(ci/{build,json-build}): support the extra label in anda.hcl (#2731) - feat(ci): fix bugs with update backporting, add weekly mode, remove f39, add el10 (#2610)

Manual backport

To create the backport manually run:

backport --pr 2792

Questions ?

Please refer to the Backport tool documentation and see the Github Action logs for details