support raw methods for azure-storage-blob

[blowsie]

Environment

Any / All

Reproduction

https://github.com/unjs/unstorage/blob/main/src/drivers/azure-storage-blob.ts#L96

Describe the bug

Calling .toString() here is problematic, as the getItem function can longer be used with buffers.

My suggestion would be to allow a type to be passed to the getItem() fn, or remove the toString() call and allow developers to call that manually, when they choose.

Additional context

No response

Logs

No response

[pi0]

Hi. We have getItemRaw that can be implemented and return the buffer/raw value. PR welcome to add that.

[blowsie]

Will do thanks!

refs ##142