Auto get the bucket region if the region is empty

[BohuTANG]

For s3, there are 3 styles URL:
https://docs.aws.amazon.com/AmazonS3/latest/userguide/access-bucket-intro.html

The last is S3://bucket-name/key-name, the bucket name does not include the AWS Region.

In OpenDAL:

opendal::services::s3::Backend::build()
.endpoint("https://bucket-name.s3.amazonaws.com")
.bucket("bucket-name")
.credential(credential)
.finish()

If we not set the region, it would be better to get it:
https://docs.aws.amazon.com/AmazonS3/latest/API/API_GetBucketLocation.html

This is used by databendlabs/databend#3586:

copy into mytable
  from 's3://bucket-name/data/files'
  credentials=(aws_key_id='$AWS_ACCESS_KEY_ID' aws_secret_key='$AWS_SECRET_ACCESS_KEY')
  encryption=(master_key = 'eSxX0jzYfIamtnBKOEOwq80Au6NbSgPH5r4BDDwOaO8=')
  file_format = (type = csv field_delimiter = '|' skip_header = 1);

[dantengsky]

• previous discussion:
  dal: Refactor to make it easier for contributors to add new storage type databendlabs/databend#3436 (comment)
• usage of GetBucketLocation
  https://docs.snowflake.com/en/user-guide/data-load-s3-config-aws-iam-user.html
  https://docs.snowflake.com/en/user-guide/data-load-s3-config-storage-integration.html
  search "s3:GetBucketLocation

[BohuTANG]

If we do it in the frontend(like Interpreter), we should import the s3 crate and call GetBucketLocation, this make the developer to know what's the dal working(This is my situation right now :D).

Looks better to do it in the dal, what's your thoughts? cc @Xuanwo

[Xuanwo]

Yep, opendal will add support for this.

[BohuTANG]

Duplicated with #56