feat: adding observable10 color scheme

[apoorvkh]

I saw that Vega supports the observable10 color scheme, which I think looks quite nice. It was added to Vega in: vega/vega#3843

I am adding this scheme to Altair's list as well.

Since, alt.Scale(scheme="observable10") currently raises a SchemaValidationError on altair==5.4.1.

[apoorvkh]

Ah, looks like that file is automatically generated by: https://github.com/vega/altair/blob/main/tools/generate_schema_wrapper.py

Before I dig further, is there any obvious reason that observable10 isn't included in the Python schema validation / typing file? Maybe Altair depends on an older version of the vega/vegalite schema?

[dangotbanned]

Ah, looks like that file is automatically generated by: main/tools/generate_schema_wrapper.py

Before I dig further, is there any obvious reason that observable10 isn't included in the Python schema validation / typing file? Maybe Altair depends on an older version of the vega/vegalite schema?

Appreciate the PR @apoorvkh!

So I did a search of https://github.com/vega/altair/blob/main/altair/vegalite/v5/schema/vega-lite-schema.json, but couldn't find any mention of "observable10".
We're currently on vega-lite/v5.20.1.json, which isn't the latest version.
However, I didn't any references to that color scheme in the past few releases https://github.com/vega/vega-lite/releases

It might be worth searching for/opening an issue in https://github.com/vega/vega-lite/issues to see if it could be added to the schema?