Fixed url construction to work with all regions

[tantona]

• added log line for debugging
• us-east-1 has a slightly different hostname so the previous url generation wasn't working for stacks in us-east-1 see https://docs.aws.amazon.com/general/latest/gr/rande.html

Signed-off-by: Alexander Tanton tantonat@amazon.com

Issue #, if available:

Description of changes:

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