$ git clone -n https://src.fedoraproject.org/rpms/qr-code-generator.git /var/lib/mock/f45-build-33998-676/root/chroot_tmpdir/scmroot/qr-code-generator
Cloning into '/var/lib/mock/f45-build-33998-676/root/chroot_tmpdir/scmroot/qr-code-generator'...
$ git fetch origin 2bf86e63b98408a0c1246ae867e20dcef9a4b7f4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/qr-code-generator
 * [new ref]         2bf86e63b98408a0c1246ae867e20dcef9a4b7f4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2bf86e6 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild