minor #7497 Reworded the intro of DI workflow article (javiereguiluz)

This PR was submitted for the master branch but it was merged into the 2.7 branch instead (closes #7497).

Discussion
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Reworded the intro of DI workflow article

This fixes #6817.

Commits
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78da359 Reworded the intro of DI workflow article

Author: xabbuh

components/dependency_injection/workflow.rst

@@ -4,8 +4,7 @@
 Container Building Workflow
 ===========================
 
-In the preceding pages of this section, there has been little to say about
-where the various files and classes should be located. This is because this
+The location of the files and classes related to the Dependency Injection
 depends on the application, library or framework in which you want to use
 the container. Looking at how the container is configured and built in the
 Symfony full-stack Framework will help you see how this all fits together,