Replaced node_redis with ioredis

test/helpers/redis.js

@@ -3,12 +3,6 @@ const cache = require('../../services/cache');
 const client = createClient();
 
 beforeEach(() => Promise.all([
-  new Promise((resolve, reject) => client.flushdb((err) => {
-    if (err) {
-      return reject(err);
-    }
-
-    return resolve();
-  })),
+  client.flushdb(),
   cache.init(),
 ]));