$ git clone -n https://src.fedoraproject.org/rpms/libdb.git /var/lib/mock/f40-build-2200124-51762/root/chroot_tmpdir/scmroot/libdb
Cloning into '/var/lib/mock/f40-build-2200124-51762/root/chroot_tmpdir/scmroot/libdb'...
$ git fetch origin 75c9099d0f6827bfe1cf811bb9a217414fec2163:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libdb
 * [new ref]         75c9099d0f6827bfe1cf811bb9a217414fec2163 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 75c9099 Additional C compatibility fixes (#2152303)