Send related emoji along with Sticker, fix SendMessage types

ts/test-both/helpers/fakeAttachment.ts

@@ -0,0 +1,15 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { AttachmentType } from '../../types/Attachment';
+import { IMAGE_JPEG } from '../../types/MIME';
+
+export const fakeAttachment = (
+  overrides: Partial<AttachmentType> = {}
+): AttachmentType => ({
+  contentType: IMAGE_JPEG,
+  width: 800,
+  height: 600,
+  size: 10304,
+  ...overrides,
+});