Root schema definition is not consistent

[AlexGacon]

The file values.schema.json states that it is possible to define 4 properties at the root level (nameOverride, fullnameOverride, releaseTrunc and prefixTrunc).

If you try to define one in the values.yaml file, we have an error message "Additional property ZZZZZ is not allowed".

It is because in the schema, the 'properties' block does not contain the list of the expected properties.