Added cards + self review

Author: mnocon

docs/discounts/configure_discounts.md

@@ -8,7 +8,7 @@ editions:
 
 # Discounts configuration
 
-You can customize the behavior of the Discounts feature using the following [configuration](configuration.md):
+You can customize the behavior of the Discounts feature by using the following [configuration](configuration.md):
 
 ## Back Office pagination
 

docs/discounts/discounts.md

@@ -16,5 +16,6 @@ You can also extend the feature, for example, by creating custom pricing rules,
 
 [[= cards([
 "discounts/discounts_guide",
-"discounts/install_discounts"
-], columns=4) =]]
+"discounts/install_discounts",
+"discounts/configure_discounts"
+], columns=3) =]]