$ git clone -n https://src.fedoraproject.org/rpms/python-widgetsnbextension.git /var/lib/mock/f40-build-2204575-51964/root/chroot_tmpdir/scmroot/python-widgetsnbextension
Cloning into '/var/lib/mock/f40-build-2204575-51964/root/chroot_tmpdir/scmroot/python-widgetsnbextension'...
$ git fetch origin c8f526e1de4de696e2866fd06a54a63a746d2b36:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-widgetsnbextension
 * [new ref]         c8f526e1de4de696e2866fd06a54a63a746d2b36 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c8f526e Convert to %autorelease and %autochangelog