[docs] fixes rst markup error

docs/userguide/signals.rst

@@ -103,7 +103,7 @@ Provides arguments:
 * declare
 
     List of entities (:class:`~kombu.Exchange`,
-    :class:`~kombu.Queue` or :class:~`kombu.binding` to declare before
+    :class:`~kombu.Queue` or :class:`~kombu.binding` to declare before
     publishing the message.  Can be modified.
 
 * retry_policy

funtests/stress/stress/app.py

@@ -64,6 +64,7 @@ def _marker(s, sep='-'):
 
 @app.task
 def add(x, y):
+    add.delay(x + x, y + y)
     return x + y