$ git clone -n https://src.fedoraproject.org/rpms/rust-gstreamer-base-sys.git /var/lib/mock/f39-build-1651235-40489/root/chroot_tmpdir/scmroot/rust-gstreamer-base-sys
Cloning into '/var/lib/mock/f39-build-1651235-40489/root/chroot_tmpdir/scmroot/rust-gstreamer-base-sys'...
$ git fetch origin 3ca8d5774708f0b9f1731e09c90002b80f9f2b72:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gstreamer-base-sys
 * [new ref]         3ca8d5774708f0b9f1731e09c90002b80f9f2b72 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3ca8d57 Update to version 0.21.1; Fixes RHBZ#2242109