request can update financial verification data

atst/models/request.py

@@ -20,6 +20,9 @@ class Request(Base):
     user_id = Column(ForeignKey("users.id"), nullable=False)
     creator = relationship("User")
 
+    task_order_id = Column(ForeignKey("task_order.id"))
+    task_order = relationship("TaskOrder")
+
     @property
     def status(self):
         return self.status_events[-1].new_status

atst/models/task_order.py

@@ -20,7 +20,7 @@ class TaskOrder(Base):
     __tablename__ = "task_order"
 
     id = Column(Integer, primary_key=True)
-    number = Column(String)
+    number = Column(String, unique=True)
     source = Column(SQLAEnum(Source))
     funding_type = Column(SQLAEnum(FundingType))
     funding_type_other = Column(String)