set label on the redis container

this ensures that redis is stopped when app is stopped and also
helps identifying app related containers easily

src/addons.js

@@ -645,6 +645,7 @@ function setupRedis(app, options, callback) {
 
     const tag = infra.images.redis.tag, redisName = 'redis-' + app.id;
     const cmd = `docker run --restart=always -d --name=${redisName} \
+                --label=appId=${app.id} --label=location=${app.location} \
                 --net cloudron \
                 --net-alias ${redisName} \
                 -m ${memoryLimit/2} \