fix(amazonq): throw if no region profiles are available

[opieter-aws]

Duplicate PR of #7357 into Flare branch

Problem

When ListRegionProfile call throttles for a subset of regions, we currently do not throw, but instead return the available profiles in the regions where the call succeeded. However, if that list is empty (no profiles in that region), we return an empty list. This breaks the UI, and causes a state that is not recoverable

Solution

Throw an error in the scenario where availableProfiles is empty. This triggers a retry state in the UI, making the state recoverable.

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[github-actions]

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[Hweinstock]

Nice! LGTM once CI passes.

[opieter-aws]

/retryBuilds