$ git clone -n https://src.fedoraproject.org/rpms/perl-Authen-Krb5.git /var/lib/mock/f40-build-733476-105247/root/chroot_tmpdir/scmroot/perl-Authen-Krb5
Cloning into '/var/lib/mock/f40-build-733476-105247/root/chroot_tmpdir/scmroot/perl-Authen-Krb5'...
$ git fetch origin 403755f9b21ac2e4069df4a6b24b1efe97047c61:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Authen-Krb5
 * [new ref]         403755f9b21ac2e4069df4a6b24b1efe97047c61 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 403755f Set build_type_safety_c to 0 (#2172836)