LPOP/RPOP with count against non existing list return null array (#10095)

It used to return `$-1` in RESP2, now we will return `*-1`.
This is a bug in redis 6.2 when COUNT was added, the `COUNT`
option was introduced in #8179. Fix #10089.

the documentation of [LPOP](https://redis.io/commands/lpop) says
```
When called without the count argument:
Bulk string reply: the value of the first element, or nil when key does not exist.

When called with the count argument:
Array reply: list of popped elements, or nil when key does not exist.
```

1 files changed, 1 insertions, 1 deletions

diff --git a/src/t_list.c b/src/t_list.c
index 460437853..4d74a1665 100644
--- a/src/t_list.c
+++ b/src/t_list.c
@@ -501,7 +501,7 @@ void popGenericCommand(client *c, int where) {
             return;
     }
 
-    robj *o = lookupKeyWriteOrReply(c, c->argv[1], shared.null[c->resp]);
+    robj *o = lookupKeyWriteOrReply(c, c->argv[1], hascount ? shared.nullarray[c->resp]: shared.null[c->resp]);
     if (o == NULL || checkType(c, o, OBJ_LIST))
         return;