minor symfony#12315 Fix typo in configuration.rst (gbirke)

This PR was merged into the 4.3 branch.

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Fix typo in configuration.rst

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913cb60 Fix typo in configuration.rst

Author: javiereguiluz

configuration.rst

@@ -505,7 +505,7 @@ In order to define the actual values of env vars, Symfony proposes different
 solutions depending if the application is running in production or in your local
 development machine.
 
-Independent from the way you set environmnet variables, you may need to run the
+Independent from the way you set environment variables, you may need to run the
 ``debug:container`` command with the ``--env-vars`` option to verify that they
 are defined and have the expected values: