Comment 4 for bug 1884944

Reviewed: https://review.opendev.org/739092
Committed: https://git.openstack.org/cgit/starlingx/tools/commit/?id=ec379155ae11b482ae59c6e5bafc75bd20720b2d
Submitter: Zuul
Branch: r/stx.3.0

commit ec379155ae11b482ae59c6e5bafc75bd20720b2d
Author: Davlet Panech <email address hidden>
Date: Mon Jun 29 10:45:31 2020 -0400

    Dockerfile: add mirror repos to global yum config

    Copy mirror repo files to /etc/yum.repos.d because tb.sh needs them.
    This change fixes a problem introduced by

      Commit: 78263e8784c5f596af2a20b9c6e214fc6fea4878
      Dockerfile: pin centos & epel repo versions

    that caused centos-mirror-tools/download_mirror.sh to fail when executed
    from a docker container created by tb.sh -- "rpm not found" for most
    packages being downloaded.

    This is because download_mirror.sh without additional arguments expects
    toCOPY/yum.repos.d/ files to have been copied to /etc/yum.repos.d/ in the
    docker container by default.

    Partial-Bug: 1884944
    Depends-On: https://review.opendev.org/#/c/737823/
    Change-Id: If214aea6560632837d0f196c21801fc2d06c8259
    Signed-off-by: Davlet Panech <email address hidden>
    (cherry picked from commit aa23b041b133c032efce238afb529e840fac58a8)