$ git clone -n https://github.com/xcp-ng-rpms/autoconf.git /var/lib/mock/v8.3-incoming-11002-29436/root/chroot_tmpdir/scmroot/autoconf
Cloning into '/var/lib/mock/v8.3-incoming-11002-29436/root/chroot_tmpdir/scmroot/autoconf'...
$ git fetch origin 2aa6fae48ec663e2c7e23f6bfea89990865b67f3:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/autoconf
 * [new ref]         2aa6fae48ec663e2c7e23f6bfea89990865b67f3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2aa6fae Add gcc-c++ to BuildRequires for check