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Documentation:
- Switch to 6.docs.plone.org (was 6.dev-docs.plone.org)
[ksuess] (497)
- Fix links to appropriate versions of docs, in preparation for redirecting docs.plone.org to 6.docs.plone.org. Fix a few typos. Use renamed tox configuration option. [stevepiercy] (498)
- Pin Sphinx<5,>=3 due to sphinx-book-theme 0.3.3 requirement. [stevepiercy] (499)
- Update links to docs to use correct versions. [stevepiercy] (500)