Fix unexpected error when creating a new cloudwatch datasource.
Involves a fair amount of refactoring, so if this causes unexpected issues related to region fetching we can turn this off with the cloudwatchNewRegionsHandler feature toggle, although we do not predict it will so we are enabling it to default to true and hope to remove it shortly.
* cleanup cloudwatch.go
* streamline interface naming
* use utility func
* rename test utils file
* move util function to where they are used
* move dtos to models
* split integration tests from the rest
* Update pkg/tsdb/cloudwatch/cloudwatch.go
Co-authored-by: Isabella Siu <Isabella.siu@grafana.com>
* refactor error codes aggregation
* move error messages to models
Co-authored-by: Isabella Siu <Isabella.siu@grafana.com>
Sarah Zinger
Will Browne
Erik Sundell