WorkflowRequest: added foreign key reference to execution_id

shared/workspaces/src/workspaces/schema.py

@@ -420,7 +420,7 @@ class WorkflowRequest(Base, WorkflowRequestIF):
     )
     argument = sa.Column("argument", sa.JSON)
     state = sa.Column("state", sa.String)
-    execution_id = sa.Column("execution_id", sa.Integer)
+    execution_id = sa.Column("execution_id", sa.Integer, sa.ForeignKey('capability_executions.id'))
     files = relationship("WorkflowRequestFile", backref="request")
 
     @property