$ git clone -n https://src.fedoraproject.org/rpms/rubygem-byebug.git /var/lib/mock/f39-build-1499230-34744/root/chroot_tmpdir/scmroot/rubygem-byebug
Cloning into '/var/lib/mock/f39-build-1499230-34744/root/chroot_tmpdir/scmroot/rubygem-byebug'...
$ git fetch origin cb67a77846792324f3892e88d5c8258f26be8d69:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-byebug
 * [new ref]         cb67a77846792324f3892e88d5c8258f26be8d69 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cb67a77 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild