minor #14055 Update routing.rst (fernandokarpinski)

This PR was merged into the 5.1 branch.

Discussion
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Update routing.rst

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Commits
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605e988 Update routing.rst

Author: OskarStark

routing.rst

@@ -1881,7 +1881,7 @@ Now, if the session is used, the application will report it based on your
 * ``enabled``: will throw an :class:`Symfony\\Component\\HttpKernel\\Exception\\UnexpectedSessionUsageException` exception
 * ``disabled``: will log a warning
 
-It well help you understanding and hopefully fixing unexpected behavior in your application.
+It will help you in understanding and hopefully fixing unexpected behavior in your application.
 
 .. _routing-generating-urls: