minor symfony#11186 Correct a sentence meaning (xuanquynh)

This PR was merged into the 3.4 branch.

Discussion
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Correct a sentence meaning

I believe that there is a mistake about passive and active sentence here. The "you are finished" clause has no meaning, doesn't it?

We can use two simple ways:
- When your work is finished,
- When you finish your work,

Commits
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06d399d Correct a sentence meaning

Author: javiereguiluz

setup/built_in_web_server.rst

@@ -135,7 +135,7 @@ you have to pass the correct location using the ``--docroot`` option:
 Stopping the Server
 -------------------
 
-When you are finished, you can simply stop the web server using the ``server:stop``
+When you finish your work, you can simply stop the web server by using the ``server:stop``
 command:
 
 .. code-block:: terminal