$ git clone -n https://src.fedoraproject.org/rpms/R-stringi.git /var/lib/mock/f42-build-861931-170512/root/chroot_tmpdir/scmroot/R-stringi
Cloning into '/var/lib/mock/f42-build-861931-170512/root/chroot_tmpdir/scmroot/R-stringi'...
$ git fetch origin a9133e2b03bf0debd67b078a07349ed8f6843f22:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-stringi
 * [new ref]         a9133e2b03bf0debd67b078a07349ed8f6843f22 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a9133e2 Rebuild for ICU 76