Fix grammar in Doc/tutorial/controlflow.rst (GH-21885) (#21922)

Automerge-Triggered-By: @csabella
(cherry picked from commit 0be7c216e16f0d459f1c8f6209734c9b2b82fbd4)

Co-authored-by: Denis Ovsienko <denis@ovsienko.info>
diff --git a/Doc/tutorial/controlflow.rst b/Doc/tutorial/controlflow.rst
index de2c73a..547f4ae 100644
--- a/Doc/tutorial/controlflow.rst
+++ b/Doc/tutorial/controlflow.rst
@@ -658,7 +658,7 @@
         return 'name' in kwds
 
 There is no possible call that will make it return ``True`` as the keyword ``'name'``
-will always to bind to the first parameter. For example::
+will always bind to the first parameter. For example::
 
     >>> foo(1, **{'name': 2})
     Traceback (most recent call last):