docs: added Override Tax Calculation Strategy doc (#3982)

docs/content/modules/taxes/overview.mdx

@@ -25,7 +25,7 @@ Admins can specify the tax provider for a specific region.
 
 Customers can view calculated taxes during their checkout process.
 
-<DocCardList colSize={6} items={[
+<DocCardList colSize={4} items={[
   {
     type: 'link',
     href: '/modules/taxes/backend/create-tax-provider',
@@ -35,6 +35,15 @@ Customers can view calculated taxes during their checkout process.
       description: 'Learn how to create a tax provider.',
     }
   },
+  {
+    type: 'link',
+    href: '/modules/taxes/backend/tax-calculation-strategy',
+    label: 'Backend: Tax Calculation Strategy',
+    customProps: {
+      icon: Icons['academic-cap-solid'],
+      description: 'Learn how to override the tax calculation strategy.'
+    }
+  },
   {
     type: 'link',
     href: '#',