minor #11030 fix services file for older version (OskarStark)

This PR was squashed before being merged into the 4.2 branch (closes #11030).

Discussion
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fix services file for older version

In the older version the file is called services.yml, which correct in the corresponding url

Commits
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5e3d47c fix services file for older version

Author: javiereguiluz

service_container.rst

@@ -1082,6 +1082,5 @@ Learn more
     /service_container/*
 
 .. _`service-oriented architecture`: https://en.wikipedia.org/wiki/Service-oriented_architecture
-.. _`Symfony Standard Edition (version 3.3) services.yaml`: https://github.com/symfony/symfony-standard/blob/3.3/app/config/services.yml
 .. _`glob pattern`: https://en.wikipedia.org/wiki/Glob_(programming)
 .. _`Symfony Fundamentals screencast series`: https://symfonycasts.com/screencast/symfony-fundamentals