Add the support of the json.arrappend command

[lieck]

This PR adds support for JSON.ARRAPEND command.
Closes #1806

[mapleFU]

General looks good to me, just some nits.

[mapleFU]

The current of CommandJsonArrAppend::Execute uses MultiBulkString. Is there a need to provide an MultiBulkInteger?

https://github.com/redis/redis-specifications/blob/master/protocol/RESP2.md#resp-integers Redis has a resp protocol, and we don't need to using "(Integer)" literal. Just using redis::Integer is ok here.

By the way, you should also add some integration test in tests/gocase. It will test the command from the client side. You can refer to unit/type/json/json_test.go

[mapleFU]

Thanks! Just few questions

[mapleFU]

Thanks @lieck . The patch lgtm!

But you still need to fix the golang-lint:

unit/type/json/json_test.go:60: File is not `gofmt`-ed with `-s` (gofmt)
	    require.NoError(t, rdb.Do(ctx, "SET", "a", `1`).Err())
        require.Error(t, rdb.Do(ctx, "JSON.ARRAPPEND", "a", "$", `1`).Err())
        require.NoError(t, rdb.Do(ctx, "DEL", "a").Err())
$ /home/runner/go/bin/golangci-lint run -v ./...
Traceback (most recent call last):

You can just run go fmt to format the file.

[mapleFU]

Thanks @lieck . I'll wait for other committers comment, and will merge it if no other doesn't have comments on this and ci passes.

[mapleFU]

cc @git-hulk @PragmaTwice

[mapleFU]

Thanks @lieck . Merged now