use region specified in the BackupStorageLocation spec to detect the Bucket region

[jala-dx]

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Fixes #(issue)
#3616

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[ashish-amarnath]

This can be simplified to keep all the region inferring/getting logic together by moving this into the default case.

default:
    region := location.Spec.Config["region"]
    var err error
    if region == "" {
        region, err = getASBucketRegion(bucket)
        if err != nil {
		url = "s3.amazonaws.com"
		break
	}
	url = fmt.Sprintf("s3-%s.amazonaws.com", region)
    }

[dsu-igeek]

Let's get rid of the switch statement altogether and just use an if/else clause. I don't think we want any additional cases here anyhow.

[ashish-amarnath]

Can you please use the PR title as the contents of the changelog?

[ashish-amarnath]

This LGTM.
I have a couple of comments.
Also, please add unit tests for this change.

[zubron]

Hi @jala-dx! Are you able to make the requested changes from @ashish-amarnath? It would be great to get this PR merged :) Thanks!

[dsu-igeek]

Let's get rid of the switch statement altogether and just use an if/else clause. I don't think we want any additional cases here anyhow.

[zubron]

I tried to make some changes to this branch so we could get this merged but unfortunately maintainers don't have write permission for the branch. I've got another branch locally which includes 40a1b62, so I will close this PR and create a new one with the original commit from this PR and my follow up changes.