Updated CHANGELOG for v2.13.2

2.13.2: another fix for the conda-forge tests (zarr-developers#1146)

See description in zarr-developers#1143
Testing locally, however, does not suffice. In this case, the relative path
in the test worked for me, but doesn't work on conda-forge. The only reliable
way to be sure is to run `./build-locally.py` in the zarr-feedstock
**against pre-tagged code**.

 2.13.1: generate fixture/meta in conda tests (zarr-developers#1143)

* 2.13.1: generate fixture/meta in conda tests

Following the pattern from zarr-developers#824, this generates the
fixture test if it does not exist so that tests will
pass on conda-forge.

see: conda-forge/zarr-feedstock#65

* Fix rst link

* Fix rst link again

* Add pragma: no cover

Prepare 2.13.0 release (zarr-developers#1133)

* Prepare 2.13.0 release

* Update release instructions for pre-releases

* Add zarr-developers#1142 for Greg's work

* Make python-version match for pre-commits

2.13.0a2 release notes (zarr-developers#1126)

* 2.13.0a2 release notes

* release note cleanup

* Make left-panel links darker

* Try rgb color

* Darken toc text and lighten background

* More light purple

* Even MORE purple!