fix(jsonschema): skips populating default if property not in instance

This commit fixes an issue in the set_default wrapper of the validator
where a property that may not be in the manifest is being set if it has
a default associated with it. This leads to inconsistencies when
attributes like additionalProperties are used.

riocli/jsonschema/validate.py

@@ -25,6 +25,11 @@ def set_defaults(validator, properties, instance, schema):
         for p, sub_schema in properties.items():
             if "default" not in sub_schema:
                 continue
+
+            # Skip if property is not in instance
+            if p not in instance:
+                continue
+
             if isinstance(instance, dict):
                 instance.setdefault(p, sub_schema["default"])
             if isinstance(instance, list):