$ git clone -n https://src.fedoraproject.org/rpms/rust-supports-color.git /var/lib/mock/f39-build-1495029-34543/root/chroot_tmpdir/scmroot/rust-supports-color
Cloning into '/var/lib/mock/f39-build-1495029-34543/root/chroot_tmpdir/scmroot/rust-supports-color'...
$ git fetch origin 5331e00fb858ca47e4d0bd64bc9211eaf91d0be3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-supports-color
 * [new ref]         5331e00fb858ca47e4d0bd64bc9211eaf91d0be3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5331e00 Update to version 2.1.0; Fixes RHBZ#2239909