fix: s3 region undefined

[trim21]

s3 doesn't always return bucket region, need to fallback to default region.

This bug is added by #1156

[aldy505]

LGTM. this means we got to do more integration testing

[prakashsvmx]

without region specified, the following is the error . so looks like the default region is not applied.

REQUEST: GET /sph-test-inc-upld?location
host: s3.amazonaws.com
user-agent: MinIO (linux; x64) minio-js/7.1.2
x-amz-date: 20230605T045033Z
x-amz-content-sha256: UNSIGNED-PAYLOAD
authorization: AWS4-HMAC-SHA256 Credential=AKIA3WNQJCXE4ABTFTFC/20230605/us-east-1/s3/aws4_request, SignedHeaders=host;x-amz-content-sha256;x-amz-date, Signature=**REDACTED**

RESPONSE: 200
x-amz-id-2: 4gitFRKsCSgBVuCB/g3jBYKGaNmY9RKUIMLED96YYMXn42l+7kVjQMOO1I+zrPqTgm/q5teFTDk=
x-amz-request-id: 4S0ZJQQD82Q6FCEE
date: Mon, 05 Jun 2023 04:50:35 GMT
content-type: application/xml
transfer-encoding: chunked
server: AmazonS3
connection: close

S3Error: 400
    at Object.parseResponseError (/home/prakash/MinIO/GIT/sdks/minio-js/dist/main/internal/xml-parser.js:81:13)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async Client.makeRequestStreamAsync (/home/prakash/MinIO/GIT/sdks/minio-js/dist/main/internal/client.js:465:19) {
  code: 'UnknownError',
  amzRequestid: '5J4QC1SBHWPYKQ5N',
  amzId2: 'Y6kK3VW9YS3LCsL0Ez0QtczQxRhI9dvOE241F5qJbkTo9kOgv/wknCQJ87hG+jNflAaWHVE0EqU=',
  amzBucketRegion: undefined,
  [cause]: {
    amzRequestid: '5J4QC1SBHWPYKQ5N',
    amzId2: 'Y6kK3VW9YS3LCsL0Ez0QtczQxRhI9dvOE241F5qJbkTo9kOgv/wknCQJ87hG+jNflAaWHVE0EqU=',
    amzBucketRegion: undefined
  }
}

[trim21]

should be fixed

import * as Minio from './src/minio.js'

var s3Client = new Minio.Client({
  endPoint: 's3.amazonaws.com',
  accessKey: '...',
  secretKey: '...',
  // region: 'us-east-1',
  // pathStyle: true,
  // useSSL: true,
})

s3Client.statObject("minio-js-test-3eb80d62-0df6-42d4-853f-e220e24ec9af-region-1", "51420856.jpg").then(o => {
  console.log(o)
}).catch(e => {
  throw e
})

[prakashsvmx]

Tested. LGTM 👍

mc mb --region=us-west-2 s3/sph-region-bucket

 ➜ mc cp ~/Pictures/10.png s3/sph-region-bucket/1.png

 var s3Client = new Minio.Client({
  endPoint: 's3.amazonaws.com',
  accessKey: 's3AccesKey',
  secretKey: 's3Secretkey,
  region: 'us-west-2',// with/without/default region.
  //pathStyle: true,
  //useSSL: true,
})

[aldy505]

LGTM