Comment 2 for bug 1939169

Reviewed: https://review.opendev.org/c/openstack/glance/+/804966
Committed: https://opendev.org/openstack/glance/commit/2a9a4c8e0e095f3cd788e2f24b2dce508538e0d5
Submitter: "Zuul (22348)"
Branch: master

commit 2a9a4c8e0e095f3cd788e2f24b2dce508538e0d5
Author: Mridula Joshi <email address hidden>
Date: Wed Aug 18 08:21:53 2021 +0000

    Fix overwriting of existing tags while creating new tags

    It was observed that md-tag-create-multiple
    (/v2/metadefs/namespaces/{namespace_name}/tags) API overwrites
    existing tags for specified namespace rather than creating new one
    in addition to the existing tags.
    This patch resolves the issue by introducing a header 'X-Openstack-Append'
    which on being True will append the new tags to existing ones and
    if False will continue to overwrite the tags.

    Implements: blueprint append-tags
    Closes-Bug: #1939169
    Change-Id: I29448746b14c542e5fbf0283011968ae1516642e