minor #10965 Remove quotes around App\Entity namespace (gsylvestre)

This PR was merged into the 4.2 branch.

Discussion
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Remove quotes around App\Entity namespace

Those quotes will appear in the generated entities namespace, thus causing a PHP ParseError.

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Commits
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a66d4d8 Remove quotes around App\Entity namespace

Author: javiereguiluz

doctrine/reverse_engineering.rst

@@ -56,7 +56,7 @@ table fields.
 
 .. code-block:: terminal
 
-    $ php bin/console doctrine:mapping:import 'App\Entity' annotation --path=src/Entity
+    $ php bin/console doctrine:mapping:import App\Entity annotation --path=src/Entity
 
 This command line tool asks Doctrine to introspect the database and generate
 new PHP classes with annotation metadata into ``src/Entity``. This generates two