$ git clone -n https://src.fedoraproject.org/rpms/jitterentropy.git /var/lib/mock/f40-build-2600730-63147/root/chroot_tmpdir/scmroot/jitterentropy
Cloning into '/var/lib/mock/f40-build-2600730-63147/root/chroot_tmpdir/scmroot/jitterentropy'...
$ git fetch origin 6bc6e9615c69a6ac3b83eebe7c0146b87737937c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jitterentropy
 * [new ref]         6bc6e9615c69a6ac3b83eebe7c0146b87737937c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6bc6e96 Update to the latest upstream v3.5.0