minor #4645 Update templates.rst: Removing duplication (ThomasLandauer)

This PR was merged into the 3.x branch.

Discussion
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Update templates.rst: Removing duplication

Page: https://twig.symfony.com/doc/3.x/templates.html#dot_operator

Reason: This is repeated a few lines further down.

Commits
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a26f43a Update templates.rst: Removing duplication

Author: fabpot

doc/templates.rst

@@ -871,9 +871,6 @@ The following operators don't fit into any of the other categories:
 
       {{ user.name }}
 
-      Twig supports a specific syntax via the ``[]`` operator for accessing items
-      on sequences and mappings, like in ``user['name']``:
-
   After the ``.``, you can use any expression by wrapping it with parenthesis
   ``()``.