The links on README.md were outdated. Updated them to replacements.

* delete docs that have been moved to docs platform

* Prepare to generate r3.10.1 release documentation

* add `[Unreleased]` entries for next releases

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Co-authored-by: Ezra Chung <88335979+eramongodb@users.noreply.github.com>

Use new docs URL, change mongodb.org to .com, fix dead links
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Co-authored-by: Ezra Chung <88335979+eramongodb@users.noreply.github.com>

Co-authored-by: bisht42 <108942387+bisht42@users.noreply.github.com>

- remove link from public README
- in release procedure documentation note that auth is required