fix: remember interaction_style in Relationship

Author: yt-ms

src/structurizr/model/relationship.py

@@ -94,6 +94,7 @@ def __init__(
         self._destination_id = destination_id
         self.description = description
         self.technology = technology
+        self.interaction_style = interaction_style
         self.linked_relationship_id = linked_relationship_id
 
         self.tags.add(Tags.RELATIONSHIP)