Move getDefaultConversation into a shared test folder

ts/test-both/helpers/getDefaultConversation.ts

@@ -0,0 +1,20 @@
+// Copyright 2020 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { v4 as generateUuid } from 'uuid';
+import { ConversationType } from '../../state/ducks/conversations';
+
+export function getDefaultConversation(
+  overrideProps: Partial<ConversationType>
+): ConversationType {
+  return {
+    id: 'guid-1',
+    lastUpdated: Date.now(),
+    markedUnread: Boolean(overrideProps.markedUnread),
+    e164: '+1300555000',
+    title: 'Alice',
+    type: 'direct' as const,
+    uuid: generateUuid(),
+    ...overrideProps,
+  };
+}