$ git clone -n https://src.fedoraproject.org/rpms/java-latest-openjdk.git /var/lib/mock/f40-build-1949415-25186/root/chroot_tmpdir/scmroot/java-latest-openjdk
Cloning into '/var/lib/mock/f40-build-1949415-25186/root/chroot_tmpdir/scmroot/java-latest-openjdk'...
$ git fetch origin bcb21f7a15f22c8d249c60f6813c4dd0b817cbca:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/java-latest-openjdk
 * [new ref]         bcb21f7a15f22c8d249c60f6813c4dd0b817cbca -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bcb21f7 April CPU