Investigate requested change around the automatic setting of the metrics primary metadata region #102
Description
There is a concern with the enable_primary_metadata_region DA input that the primary metadata region might change frequently if different instances of the DA are provisioned in the same account.
Consumers may not realise they are doing this (since the default is set to true) and it having metadata stored in different regions may have compliance concerns.
The reason it was added in the first place is because if there is no primary metadata region set on an account yet, metrics routing target creation will fail with:
Error: CreateTargetWithContext failed Your request has failed because metadata_primary_region in settings is empty. Please set the metadata_region_primary and then try again.
We have been asked to investigate if we could only set the primary metadata region in the DA if there is none set. If there is one already set, do not override it (perhaps we provide a way explicitly to "opt in" instead).
Conditionally configuring resources (or settings in this case) in terraform based on the outcome of some other logic has its own limitations around no knowing an exact count before apply time - so we may need to think outside the box here.