$ git clone -n https://src.fedoraproject.org/rpms/rust-pango-sys0.21.git /var/lib/mock/f45-build-43690-805/root/chroot_tmpdir/scmroot/rust-pango-sys0.21
Cloning into '/var/lib/mock/f45-build-43690-805/root/chroot_tmpdir/scmroot/rust-pango-sys0.21'...
$ git fetch origin 21618e732f5540bd220870b05b9e3d8e195bc616:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-pango-sys0.21
 * [new ref]         21618e732f5540bd220870b05b9e3d8e195bc616 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 21618e7 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild