Make composite unit test an unrealistic test scenario about undefined ids

Also make the thrown error suggest how to fix the problem.

Co-authored-by: Janne Savolainen <janne.savolainen@live.fi>

Signed-off-by: Iku-turso <mikko.aspiala@gmail.com>

src/common/utils/composite/get-composite/get-composite.test.ts

@@ -287,7 +287,7 @@ Available parent ids are:
 
     const items = [root, someItem, someOtherItem];
 
-    const getComposite = getCompositeFor<SomeItem>({
+    const getComposite = getCompositeFor<any>({
       getId: (x) => x.id,
       getParentId: (x) => x.parentId,
     });