$ git clone -n https://src.fedoraproject.org/rpms/rust-time-core /var/lib/mock/f42-build-3430631-45393/root/chroot_tmpdir/scmroot/rust-time-core
Cloning into '/var/lib/mock/f42-build-3430631-45393/root/chroot_tmpdir/scmroot/rust-time-core'...
$ git fetch origin 0f0f3d6807369a9df43a024e9f285cce8d2bc955:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-time-core
 * [new ref]         0f0f3d6807369a9df43a024e9f285cce8d2bc955 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0f0f3d6 Update to version 0.1.3; Fixes RHBZ#2350045