message: Correct context binding
diff: @@ -708,14 +708,15 @@ export class GraphQLModule<Config = any, Session = any, Context = any> {
  }
  };
  - const { onConnect, onDisconnect } = this.selfSubscriptionHooks;
  + const subscriptionHooks = this.selfSubscriptionHooks;
  + const { onConnect, onDisconnect } = subscriptionHooks;
  this._cache.subscriptionHooks = {
  onConnect: async (connectionParams, websocket, context) => {
  const importsResultArr$ = [...importsSubscriptionHooks].map(async ({ onConnect }) => onConnect ? onConnect(connectionParams, websocket, context) : {});
  const importsResultArr = await Promise.all(importsResultArr$);
  const importsResult = importsResultArr.reduce((acc, curr) => ({ ...acc, ...curr}), {} as any);
  - const moduleResult = onConnect ? await onConnect(connectionParams, websocket, context) : {};
  + const moduleResult = onConnect ? await onConnect.call(subscriptionHooks, connectionParams, websocket, context) : {};
  return {
  ...importsResult,
  ...moduleResult,
  @@ -725,7 +726,7 @@ export class GraphQLModule<Config = any, Session = any, Context = any> {
  const importsResultArr$ = [...importsSubscriptionHooks].map(async ({ onDisconnect }) => onDisconnect ? onDisconnect(websocket, context) : {});
  const importsResultArr = await Promise.all(importsResultArr$);
  const importsResult = importsResultArr.reduce((acc, curr) => ({ ...acc, ...curr}), {} as any);
  - const moduleResult = onDisconnect ? await onDisconnect(websocket, context) : {};
  + const moduleResult = onDisconnect ? await onDisconnect.call(subscriptionHooks, websocket, context) : {};
  return {
  ...importsResult,
  ...moduleResult,
  