$ git clone -n https://src.fedoraproject.org/rpms/ruby-build.git /var/lib/mock/f45-build-34739-691/root/chroot_tmpdir/scmroot/ruby-build
Cloning into '/var/lib/mock/f45-build-34739-691/root/chroot_tmpdir/scmroot/ruby-build'...
$ git fetch origin 8856f1a3fe689e6b9ccd436805a8f45634442b10:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ruby-build
 * [new ref]         8856f1a3fe689e6b9ccd436805a8f45634442b10 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8856f1a Update to 20260716 upstream release