minor #15431 Typo (askeita)

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

Discussion
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Typo

Removed extra spacing between 'step' and 'by'.

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Commits
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c5d30b2 Typo

Author: javiereguiluz

deployment.rst

@@ -7,8 +7,7 @@ How to Deploy a Symfony Application
 ===================================
 
 Deploying a Symfony application can be a complex and varied task depending on
-the setup and the requirements of your application. This article is not a step-
-by-step guide, but is a general list of the most common requirements and ideas
+the setup and the requirements of your application. This article is not a step-by-step guide, but is a general list of the most common requirements and ideas
 for deployment.
 
 .. _symfony2-deployment-basics: