Add link to anything-goes

[mattwthompson]

• Add link to anything-goes at the bottom of the examples page
• Copy "no warranty" line from README
• Make it abundantly clear that these are not "off-the-shelf" examples
• Repeatedly emphasize that these are not production-quality examples
• Additionally communicate that most examples are probably broken

[github-actions]

This repository caches data generated from notebooks stored in other repositories in the _cookbook_data_* branches. Regenerating this cache takes about half an hour, so it is not done automatically in PRs. The current value of the cache from the main branch has been copied over to this PR's cache.

To regenerate the cache for this PR, create a comment on this PR consisting only of the string:

/regenerate-cache

[jameseastwood]

This language conveys the right message.

[mattwthompson]

Did an eyeball check on the rendered form before merging:

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