$ git clone -n https://src.fedoraproject.org/rpms/notmuch.git /var/lib/mock/f42-build-3403714-45135/root/chroot_tmpdir/scmroot/notmuch
Cloning into '/var/lib/mock/f42-build-3403714-45135/root/chroot_tmpdir/scmroot/notmuch'...
$ git fetch origin 7abd7d78d30dba016f17d442fe3010a6b8ea46cd:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/notmuch
 * [new ref]         7abd7d78d30dba016f17d442fe3010a6b8ea46cd -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7abd7d7 Rebuilt for https://fedoraproject.org/wiki/Fedora_42_Mass_Rebuild