fixup! build: enforce consistent readonly array type

Author: rafaelss95

src/components-examples/material/chips/chips-input/chips-input-example.ts

@@ -19,7 +19,7 @@ export class ChipsInputExample {
   selectable = true;
   removable = true;
   addOnBlur = true;
-  separatorKeysCodes = [ENTER, COMMA] as const;
+  readonly separatorKeysCodes = [ENTER, COMMA];
   fruits: Fruit[] = [
     {name: 'Lemon'},
     {name: 'Lime'},