Issue 7136 - Derive AWS domain suffix from region

[patchwork01]

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  • Resolves Detect AWS domain suffix automatically #7136

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[patchwork01]

I'm going to put this on hold and wait for confirmation on whether IAM Service Principals need the DNS suffix or should be left as amazonaws.com.

[patchwork01]

Actually, I'll revert the service principal changes and make a separate issue for that.

Patchwork has further changes they wish to make

[patchwork01]

I changed my mind, I don't want to change anything. We can leave the service principals with the DNS suffix included unless it turns out they need to change.

[patchwork01]

The service principals actually should stay as amazonaws.com. I'm reverting those.

[patchwork01]

I've just gone through and found the places where the service principal is derived from the DNS suffix.