$ git clone -n https://src.fedoraproject.org/rpms/R-htmlwidgets.git /var/lib/mock/f40-build-1944482-25177/root/chroot_tmpdir/scmroot/R-htmlwidgets
Cloning into '/var/lib/mock/f40-build-1944482-25177/root/chroot_tmpdir/scmroot/R-htmlwidgets'...
$ git fetch origin 7b32955ad1fcfd954904f5e2ec97e0454d336820:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-htmlwidgets
 * [new ref]         7b32955ad1fcfd954904f5e2ec97e0454d336820 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7b32955 R-maint-sig mass rebuild