check_package_exists was only checking name+version+release, so an
almalinux package already in Gitea would cause fedora builds to be
skipped incorrectly.
Now passes the target distro from PackageInfo through to
check_package_exists, which maps it to an RPM dist suffix (.el9,
.fc43, etc.) and queries the Gitea package files endpoint to confirm
a distro-specific file exists before skipping the build.
Also adds fedora/42, fedora/43, fedora/44 to the allowed repository
values in the metadata schema.
unkinben
9ca3340f10