$ git clone -n https://src.fedoraproject.org/rpms/perl-ExtUtils-CppGuess.git /var/lib/mock/f45-build-23372-597/root/chroot_tmpdir/scmroot/perl-ExtUtils-CppGuess
Cloning into '/var/lib/mock/f45-build-23372-597/root/chroot_tmpdir/scmroot/perl-ExtUtils-CppGuess'...
$ git fetch origin 4157ad5f969db3e59f42d5ec312ada2a665f6c59:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-ExtUtils-CppGuess
 * [new ref]         4157ad5f969db3e59f42d5ec312ada2a665f6c59 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4157ad5 0.271 bump (rhbz#2510949)