Fixes#2106
Docs are now hosted as part of the frontend at `/docs` by default.
- If `docs_url` is set in the helm chart, the `/docs` endpoint will
redirect to that endpoint instead
- Use multi-stage python image to build mkdocs as part of frontend, then
copy static output
- Dir layout: mkdocs.yml and docs into frontend/docs
- CI: Update docs build GH action to use new path
- Update all frontend paths to use `/docs/` instead of
`https://docs.browsertrix.com/`
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Co-authored-by: Henry Wilkinson <henry@wilkinson.graphics>
c33f749515