$ git clone -n https://src.fedoraproject.org/rpms/picom.git /var/lib/mock/f41-build-857922-168262/root/chroot_tmpdir/scmroot/picom
Cloning into '/var/lib/mock/f41-build-857922-168262/root/chroot_tmpdir/scmroot/picom'...
$ git fetch origin 3845e217e24e659d25188af5196ca9109ffe71e4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/picom
 * [new ref]         3845e217e24e659d25188af5196ca9109ffe71e4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3845e21 Update to 12.1 upstream release