Installation Guide Routes Importing Step Correction (#463)

| Q               | A
| --------------- | -----
| Branch?         |  1.6

Author: GSadee

docs/legacy_installation.md

@@ -21,12 +21,12 @@
     imports:
         - { resource: "@SyliusRefundPlugin/Resources/config/app/config.yml" }
     ```
-1. Import routing:
+1. Import routes:
 
-    ````yaml
+    ```yaml
     sylius_refund:
         resource: "@SyliusRefundPlugin/Resources/config/routing.yml"
-    ````
+    ```
 
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