$ git clone -n https://src.fedoraproject.org/rpms/perl-Email-MIME-Kit.git /var/lib/mock/f45-build-23307-596/root/chroot_tmpdir/scmroot/perl-Email-MIME-Kit
Cloning into '/var/lib/mock/f45-build-23307-596/root/chroot_tmpdir/scmroot/perl-Email-MIME-Kit'...
$ git fetch origin 6b233718638611f1ab8f8ea4ea20b8e02c6b4edb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Email-MIME-Kit
 * [new ref]         6b233718638611f1ab8f8ea4ea20b8e02c6b4edb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6b23371 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild