fix redis no such key (#1647)

### What problem does this PR solve?
fix Redis no such key #1614

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

---------

Signed-off-by: seaver <zhudan187@qq.com>
Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>

rag/utils/redis_conn.py

@@ -44,9 +44,14 @@ class RedisDB:
             logging.warning("Redis can't be connected.")
         return self.REDIS
 
-    def health(self, queue_name):
+    def health(self):
+
         self.REDIS.ping()
-        return self.REDIS.xinfo_groups(queue_name)[0]
+        a, b = 'xx', 'yy'
+        self.REDIS.set(a, b, 3)
+
+        if self.REDIS.get(a) == b:
+            return True
 
     def is_alive(self):
         return self.REDIS is not None