Remove yamale

[stsewd]

Closes #8549

[ericholscher]

It seems like the original concept here was to replace this with jsonschema -- is that already done, or are we replacing this with pydantic?

[stsewd]

It seems like the original concept here was to replace this with jsonschema -- is that already done, or are we replacing this with pydantic?

Pydantic is a better choice, it also supports generating a json schema from the classes :) (hopefully we can use it without any manual changes).