Support formatting angular syntax in markdown (#18519)

tests/format/markdown/code/angular/angular-html.md

@@ -0,0 +1,8 @@
+```angular-html
+@if (orderForm.couponCode().disabled()) {
+      <div class="info">
+        @for (reason of orderForm.couponCode().disabledReasons(); track reason) {
+<p>{{ reason.message }}</p>
+        }</div>
+    }
+```