Generate automatic CHANGELOG from release note and add it to docs

[JulioAPeraza]

Closes #603 .

Changes proposed in this pull request:

• Generate automatic CHANGELOG from release note.
• Add CHANGELOG to documentation.

[tsalo]

One question- will the release notes for the current release appear in that release's changelog file, or will it show up in the next release?

[JulioAPeraza]

I'm not sure. Let me check what action will run this workflow. If is the later, do you think we can add your changelog from here and use the changes of this PR for future releases?

[tsalo]

We can definitely build the changelog from old releases manually. I'm more concerned that each release might be missing its own release notes. So if you went to the RTD build for v0.20.0, you would only see a changelog covering v0.0.1-v0.19.0, without the changes that went into v0.20.0.

[codecov]

Codecov Report

Merging #684 (44f709a) into main (744bc0d) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #684   +/-   ##
=======================================
  Coverage   85.32%   85.32%           
=======================================
  Files          41       41           
  Lines        4503     4503           
=======================================
  Hits         3842     3842           
  Misses        661      661           

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[JulioAPeraza]

I wasn't able to test this workflow or automatically add previous release notes in this PR because the CHANGELOG.md does not exist in the neurostuff:main and JulioAPeraza:auto-changelog doesn't contain releases. Would it be OK to test this in a separate PR after this one is merged?

[tsalo]

I'm happy to test it on main and then fix it up in a later PR if necessary. I'll merge this now.

We can make an rc release this week to test it.