Missing schema property for `anchors`

[esteban-gs]

The docs here mention the support for anchors, but the yaml schema does not include it: https://docs.getdbt.com/reference/resource-properties/anchors.

The schema: https://github.com/dbt-labs/dbt-jsonschema/blob/main/schemas/latest/dbt_yml_files-latest.json.

There is a mention of anchors in https://github.com/dbt-labs/dbt-jsonschema/blob/main/schemas/latest_fusion/dbt_yml_files-latest-fusion.json, but the severity enums, "Error", "Warn" are not valid by the other schema's definitions.