For 1.8.16 release

[SpacemanPaul]

Reason for this pull request

Prepare for 1.8.16 release.

Proposed changes

• Update whats_new.rst for release.

• Manually apply recent Dependabot upgrades.

  • [x] Tests added / passed
  • [x] Fully documented, including docs/about/whats_new.rst for all changes

---

:books: Documentation preview :books:: https://datacube-core--1501.org.readthedocs.build/en/1501/

[codecov[bot]]

Codecov Report

All modified lines are covered by tests :white_check_mark:

Comparison is base (584db42) 91.75% compared to head (2852bae) 91.75%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #1501 +/- ## ======================================== Coverage 91.75% 91.75% ======================================== Files 132 132 Lines 14549 14549 ======================================== Hits 13350 13350 Misses 1199 1199 ```

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