minor #19983 Update best_practices.rst, add /routes (tacman)

This PR was submitted for the 7.1 branch but it was merged into the 5.4 branch instead.

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Update best_practices.rst, add /routes

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3a5f779 Update best_practices.rst, add /routes

Author: javiereguiluz

best_practices.rst

@@ -51,6 +51,7 @@ self-explanatory and not coupled to Symfony:
     │  └─ console
     ├─ config/
     │  ├─ packages/
+    │  ├─ routes/
     │  └─ services.yaml
     ├─ migrations/
     ├─ public/