add bull queue

.env.example

@@ -25,6 +25,9 @@ JWT_PROVIDER_AUTH_LIFETIME=
 # Required
 MONGO_URL=mongodb://root:example@mongo:27017/?authSource=admin
 
+# Redis
+REDIS_URL=redis://redis:6379
+
 # Optional credentials for MongoDB container instance and Mongo-Express
 MONGO_USERNAME=root
 MONGO_PASSWORD=example