Use buildEvent function in more places

references.test.ts

@@ -1,10 +1,8 @@
 import {parseReferences} from '.'
+import { buildEvent } from './test-helpers'
 
 test('parse mentions', () => {
-  let evt = {
-    kind: 1,
-    id: '',
-    pubkey: '',
+  let evt = buildEvent({
     tags: [
       [
         'p',
@@ -25,9 +23,7 @@ test('parse mentions', () => {
     ],
     content:
       'hello #[0], have you seen #[2]? it was made by nostr:nprofile1qqsvc6ulagpn7kwrcwdqgp797xl7usumqa6s3kgcelwq6m75x8fe8yc5usxdg on nostr:nevent1qqsvc6ulagpn7kwrcwdqgp797xl7usumqa6s3kgcelwq6m75x8fe8ychxp5v4! broken #[3]',
-    created_at: 0,
-    sig: '',
-  }
+  })
 
   expect(parseReferences(evt)).toEqual([
     {