Changelog has gone missing

[Tim McCormack]

- [x] This doc is inaccurate in this way: README.rst links to changelog, but changelog is missing from docs site
- [ ] This is a doc addition request.
- [ ] I have a fix to the document that I can paste below including example: input and output.

Historically, a changelog has been present at https://docs.openstack.org/pbr/latest/user/history.html -- this is linked to from https://opendev.org/openstack/pbr/src/branch/master/README.rst and consequently from the PyPI description as well. However, it is now a 404, and there is no clear replacement.

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Release: on 2018-09-24 11:58:46
SHA: c85bf5e77f5c4762a2963e1c0023a90ab62394ce
Source: https://opendev.org/openstack/pbr/src/doc/source/index.rst
URL: https://docs.openstack.org/pbr/latest/