Add NOVALUES support to HSCAN

[Rueian]

Ref: redis/go-redis#2919

Suggested change:

Add a NOVALUES block to the end of:

rueidis/hack/cmds/commands.json

Lines 2993 to 3016 in 236216b

 "HSCAN": { 
   "summary": "Incrementally iterate hash fields and associated values", 
   "complexity": "O(1) for every call. O(N) for a complete iteration, including enough command calls for the cursor to return back to 0. N is the number of elements inside the collection..", 
   "arguments": [ 
     { 
       "name": "key", 
       "type": "key" 
     }, 
     { 
       "name": "cursor", 
       "type": "unsigned integer" 
     }, 
     { 
       "command": "MATCH", 
       "name": "pattern", 
       "type": "pattern", 
       "optional": true 
     }, 
     { 
       "command": "COUNT", 
       "name": "count", 
       "type": "integer", 
       "optional": true 
     } 

and then run go generate

---

The NOVALUES block should look like:

      {
        "name": "NOVALUES",
        "type": "pure-token",
        "token": "NOVALUES",
        "optional": true
      }