minor #4664 Spelling mistake tens to tons (albabar)

This PR was submitted for the 2.6 branch but it was merged into the 2.3 branch instead (closes #4664).

Discussion
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Spelling mistake tens to tons

I'm not sure, but I think it should be tons, not tens.

Commits
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299cc2e Spelling mistake tens to tons

Author: wouterj

quick_tour/the_architecture.rst

@@ -246,7 +246,7 @@ the Twig templating system and some other third party libraries and bundles.
 Understanding the Cache and Logs
 --------------------------------
 
-Symfony applications can contain tens of configuration files defined in several
+Symfony applications can contain several configuration files defined in several
 formats (YAML, XML, PHP, etc.) Instead of parsing and combining all those files
 for each request, Symfony uses its own cache system. In fact, the application
 configuration is only parsed for the very first request and then compiled down