Define Netlify CI variables in netlify.toml

[yubiuser]

What does this PR aim to accomplish?:

We just switched to Ubuntu Noble 24.04 which uses an up-to-date python (3.12) by default. See #1189 (comment)

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[yubiuser]

@PromoFaux

Are there any site environment variables set in Netlify's UI? Because it's still using Python 3.8

[PromoFaux]

yeah, it was set to 3.8. Have changed it to 3.12 - try again!

[yubiuser]

Thanks. With the second commit I've set it via netlify.toml to 3.11 which matches the version we have on CI.

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I think I prefer to set it via config file instead of having it in the Netlify UI - It's easier to keep it up-to-date and not forget about it.
Renaming runtime.txt > netlify.toml still seems to be a good move because it's easier to understand what the file is for.

[XhmikosR]

If you are going with this, I suggest that you move all env vars and settings in runtime.txt and remove them from Netlify UI. That way everything will be handled in one place.

Other settings are Node version, build command, folder and maybe more.

[yubiuser]

I added all other environment variables defined in Netlify's UI to the netlify.toml

[XhmikosR]

How about build command and directory?

Also, will your settings work for branch deployments? I notice you used context.deploy-preview.environment only; I don't know if Netlify is using the same key for branch builds like production, too.

[yubiuser]

Can squash down when desired

[XhmikosR]

See also https://docs.netlify.com/configure-builds/file-based-configuration/#build-settings

Both mkdocs build --strict or npm run build will work, I guess it makes more sense to use mkdocs build --strict on Netlify since Node.js isn't really needed.