Preserve Angular control flow syntax in ngNonBindable directive (#20066)

Co-authored-by: fisker <lionkay@gmail.com>

changelog_unreleased/angular/20066.md

@@ -0,0 +1,20 @@
+#### Preserve Angular syntax inside elements with `ngNonBindable` directive (#20066 by @splincode)
+
+<!-- prettier-ignore -->
+```html
+<!-- Input -->
+<span ngNonBindable>@if(foo){bar}</span>
+<span ngNonBindable>@let foo=bar+baz;</span>
+
+<!-- Prettier stable -->
+<span ngNonBindable>
+  @if (foo) {
+    bar
+  }
+</span>
+<span ngNonBindable>@let foo = bar + baz;</span>
+
+<!-- Prettier main -->
+<span ngNonBindable>@if(foo){bar}</span>
+<span ngNonBindable>@let foo=bar+baz;</span>
+```