ref: Deprecate pass message component (#8351)

* Update pass_message.py

* Update src/backend/base/langflow/components/logic/pass_message.py

Co-authored-by: Eric Hare <ericrhare@gmail.com>

---------

Co-authored-by: Eric Hare <ericrhare@gmail.com>
Co-authored-by: Yuqi Tang <yuqi.tang@datastax.com>

src/backend/base/langflow/components/logic/pass_message.py

@@ -9,6 +9,7 @@ class PassMessageComponent(Component):
     description = "Forwards the input message, unchanged."
     name = "Pass"
     icon = "arrow-right"
+    legacy: bool = True
 
     inputs = [
         MessageInput(