adjust info about binding keys (they must be present)

Author: Samik081

messenger.rst

@@ -1671,7 +1671,7 @@ The transport has a number of options:
     Binding direction: source exchange -> this exchange
 
 ``exchange[bindings][binding_keys]``
-    The binding/routing keys (if any) to be used for the binding
+    The binding/routing keys to be used for the binding
 
 ``exchange[bindings][binding_arguments]``
     Additional binding arguments