Request to improve deployment instructions in README.md - aws s3api create-bucket fails

[alistairpullen]

Section:

3. Create a staging S3 bucket
   The staging bucket is required to store the SAM deployment artifacts. The name I chose for my s3 bucket is rpcme-dx-monitor
   aws s3api create-bucket --bucket rpcme-dx-monitor

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The command returns the following error:
An error occurred (IllegalLocationConstraintException) when calling the CreateBucket operation: The unspecified location constraint is incompatible for the region specific endpoint this request was sent to.

Rather replace with the following working command:
$ aws s3 mb s3://rpcme-dx-monitor --region us-west-1