add test for bot signal

__mocks__/matrix-js-sdk.js

@@ -157,6 +157,10 @@ export const mockGetGroupUsers = jest.fn(() => {
 
 export const mockGetUser = jest.fn().mockReturnValue({ presence: 'online'});
 
+export const mockSendStateEvent = jest.fn(() => {
+  return Promise.resolve();
+});
+
 export const mockClient = {
   registerRequest: mockRegisterRequest,
   initCrypto: mockInitCrypto,
@@ -186,6 +190,7 @@ export const mockClient = {
   getJoinedRoomMembers: mockGetJoinedRoomMembers,
   getUser: mockGetUser,
   getGroupUsers: mockGetGroupUsers,
+  sendStateEvent: mockSendStateEvent,
 }
 
 export const WebStorageSessionStore = jest.fn()