allergies: Update to canonical data

Test case - allergic to eggs in addition to other stuff is incomplete.
Add checks for shellfish and strawberries.

exercises/allergies/src/test/java/AllergiesTest.java

         Allergies allergies = new Allergies(5);
 
         assertEquals(true, allergies.isAllergicTo(Allergen.EGGS));
+        assertEquals(true, allergies.isAllergicTo(Allergen.SHELLFISH));
+        assertEquals(false, allergies.isAllergicTo(Allergen.STRAWBERRIES));
     }
 
     @Ignore