Update the command json to forbid cross slots in PUBSUB SHARDNUMSUB

[rueian]

We should not allow passing cross slots channel names to the command builder of the PUBSUB SHARDNUMSUB command.

See valkey-io/valkey#1369 (comment)

Todos:

Update the type from string to key.

valkey-go/hack/cmds/commands.json

Lines 4777 to 4781 in 33b2879

	"PUBSUB SHARDNUMSUB": {
	"arguments": [
	{
	"name": "channel",
	"type": "string",

Then regenerate the command builder by running go generate.

[zuiderkwast]

If it's just a string now, do you route it to the correct node already? Let's say when it's called with only one shard channel.

[rueian]

It doesn’t unfortunately. It will only be route correctly after we change the type to key and regenerate the corresponding code.

[fscnick]

Hi @rueian, I'd like to help with this issue.