erlcloud_s3 can't access a object by sign v4 url
(please see https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-query-string-auth.html).
I add erlcloud_s3:make_presigned_v4_url function, it return a presigned (v4) url and we can use this url download private s3 object directly #560

Thank you.