1.0a8 release notes and upgrade instructions

[simonw]

This alpha has a breaking change which needs to be clearly documented - the way it refuses plugins in metadata.json now.

[simonw]

I should describe https://github.com/datasette/datasette-test as a way to help upgrade plugin tests for this breaking change.

[simonw]

Commits so far: 1.0a7...2e4a03b

[simonw]

I'm going to start a whole new page of documentation, docs/upgrades.rst, where upgrade instructions for breaking changes can live independently from general release notes.

[simonw]

.. _v1_0_a8:

1.0a8 (2024-02-01)
------------------

...

[simonw]

Thanks to #2248 I don't need that docs/upgrades.rst page for this.

[simonw]

Some questions that came up for me while working on the release notes:

• Treat allow blocks in metadata as if they were in config #2249
• Are canned queries defined in metadata or config now? Maybe I need a upgrades.rst document to explain that after all? Relevant commit: 35deaab#diff-3a699b24fbeec5074c92e7479c1ef901c5eee0817779ca07225d7939fea188c1L351
• JavaScript plugin hooks need documentation: 452a587

[simonw]

I'm going to work on these in a PR.