minor #16484 [Config] Suggest avoiding new environments (runephilosof-abtion)

This PR was submitted for the 6.0 branch but it was squashed and merged into the 4.4 branch instead.

Discussion
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[Config] Suggest avoiding new environments

Inspired by https://12factor.net/config

Commits
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de68147 [Config] Suggest avoiding new environments

Author: javiereguiluz

configuration.rst

@@ -464,6 +464,10 @@ going to production:
     It's common for environments to be similar to each other, so you can
     use `symbolic links`_ between ``config/packages/<environment-name>/``
     directories to reuse the same configuration.
+    
+    There are benefits to separating configuration from code. So try to avoid
+    creating new environments and instead set environment variables.
+    This way it is easy to add another environment for staging/qa/review applications.
 
 .. _config-env-vars: