Fix AWS API error on us-east-1 CreateBucket

[0x2b3bfa0]

Fixes the latest variation of the #455 nightmare, when running s3:CreateBucket on the us-east-1 region.

Error: operation error S3: CreateBucket, https response error StatusCode: 400, RequestID: ..., HostID: ..., api error MalformedXML: The XML you provided was not well-formed or did not validate against our published schema

When running PUT https://{bucket}.s3.us-east-1.amazonaws.com with no options, the request body should be empty, like in Content-Lenght: 0 empty.

Before this pull request, the body had an empty XML document:

<CreateBucketConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/"></CreateBucketConfiguration>

[casperdcl]

(re) fixes #454 (or at least the us-east bit).

Should we add e2e us-east tests to catch this? Seems us-east can be a bit cheaper than us-west (by ~20% on g4dn.xlarge for example)

[0x2b3bfa0]

This pull request doesn't fix that issue, it fixes a different issue that happens when performing the same action. Anyway, I feel nitpicky today. 😄

[0x2b3bfa0]

Should we add tests to catch this?

We can move our tests to us-east-1 but they're going to be slower. 🤷🏼‍♂️ I hope that this time we fix the issue for real.

[casperdcl]

tested; working thx