minor #14733 [DependencyInjection] [Service Container] Fix typo in tag default index method name (nemoipaha)

This PR was merged into the 4.4 branch.

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[DependencyInjection] [Service Container] Fix typo in tag default index method name

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dc072c4 [Service Container] Fix typo in tag default index method name

Author: OskarStark

service_container/tags.rst

@@ -807,7 +807,7 @@ array element. For example, to retrieve the ``handler_two`` handler::
 .. tip::
 
     Just like the priority, you can also implement a static
-    ``getDefaultIndexAttributeName()`` method in the handlers and omit the
+    ``getDefaultIndexName()`` method in the handlers and omit the
     index attribute (``key``)::
 
         // src/Handler/One.php