$ git clone -n https://src.fedoraproject.org/rpms/R-rJava.git /var/lib/mock/f40-build-789598-135922/root/chroot_tmpdir/scmroot/R-rJava
Cloning into '/var/lib/mock/f40-build-789598-135922/root/chroot_tmpdir/scmroot/R-rJava'...
$ git fetch origin 320ce792a4d39195868eeff5f6b002db0fa3f39e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-rJava
 * [new ref]         320ce792a4d39195868eeff5f6b002db0fa3f39e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 320ce79 Rebuilt for java-21-openjdk as system jdk