Add one more dummy item to the mock file

Author: SmolinPavel

src/ContextPresentation/Shared/mock.js

@@ -15,5 +15,6 @@ export const messages = [
   { id: 14, text: 'Dummy text 13' },
   { id: 15, text: 'Dummy text 14' },
   { id: 16, text: 'Dummy text 15' },
-  { id: 17, text: 'Dummy text 16' }
+  { id: 17, text: 'Dummy text 16' },
+  { id: 18, text: 'Dummy text 17' }
 ];