minor symfony#15525 Update best_practices.rst (steveclifton)

This PR was submitted for the 5.3 branch but it was merged into the 4.4 branch instead.

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Update best_practices.rst

Add missing text to sentence to improve readability

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e329db9 Update best_practices.rst

Author: javiereguiluz

best_practices.rst

@@ -170,7 +170,7 @@ Use Autowiring to Automate the Configuration of Application Services
 
 :doc:`Service autowiring </service_container/autowiring>` is a feature that
 reads the type-hints on your constructor (or other methods) and automatically
-passes the correct services to each method, making unnecessary to configure
+passes the correct services to each method, making it unnecessary to configure
 services explicitly and simplifying the application maintenance.
 
 Use it in combination with :ref:`service autoconfiguration <services-autoconfigure>`