Implement detection rule for changing type of additional properties

[macisamuele]

Change value of additionalProperties

Rationale

If the object is defined with additionalProperties set to False then the object will not allow presence of properties not defined on the properties section of the object definition. Changing the value of additionalProperties could lead to incompatible changes when the new specs define a less stringent requirement.

Mitigation

TODO

The main goal is to identify changes like

• {...} -> {"additionalProperties": False, ...}
• {...} -> {"additionalProperties": {xxx}, ...}
• {"additionalProperties": {...}, ...} -> {"additionalProperties": {something different}, ...}
• etc