$ git clone -n https://src.fedoraproject.org/rpms/gthumb.git /var/lib/mock/f40-build-2290252-55963/root/chroot_tmpdir/scmroot/gthumb
Cloning into '/var/lib/mock/f40-build-2290252-55963/root/chroot_tmpdir/scmroot/gthumb'...
$ git fetch origin 4fe7ac4f3ff152b2d97399347197c1652f63efc1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gthumb
 * [new ref]         4fe7ac4f3ff152b2d97399347197c1652f63efc1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4fe7ac4 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild