$ git clone -n https://src.fedoraproject.org/rpms/R-httr.git /var/lib/mock/f38-build-side-42-init-devel-1079995-29825/root/chroot_tmpdir/scmroot/R-httr
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1079995-29825/root/chroot_tmpdir/scmroot/R-httr'...
$ git fetch origin 9f420fdf6e14d230c8290f1eba947d8738c49fe7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-httr
 * [new ref]         9f420fdf6e14d230c8290f1eba947d8738c49fe7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9f420fd update to 1.4.5