Bucket: generic bucket provider support custom url lookup type

[zhiyu0729]

The bucket provider I am currently using is Alibaba Cloud's oss, which is an object storage compatible with the S3 protocol. But OSS only supports virtual hosted style access to buckets. I see that the lookup method of the bucket is hard-coded now

source-controller/pkg/minio/minio.go

Line 43 in 36ca723

BucketLookup: minio.BucketLookupPath,

This makes it impossible to use it with oss.

I think we can use auto lookup type or add bucket.Spec.LookupType to Bucket api to make it configurable

[yusupovazubaljat]

very good