Validating instance types for RDS

[evilensky]

Would cfn-lint catch something like trying to deploy Aurora mysql 8.0 on an unsupported instance type?

Edit: The X to the Y is we'd like to validate this exact scenario before we attempt a CF deploy, without keeping a matrix of support ourselves. Wondering if inserting this into our CD would make sense, for this specific scenario and any other matrixes of supported instances (Elasticache?)

[PatMyron]

scripts/update_specs_from_pricing.py maintains data/AdditionalSpecs/RdsProperties.json which is used by rule E3025 to validate that for RDS

Matrix validation isn't yet covered for other AWS database services. Those services just validate supported engines and instance types separately without knowing unsupported combinations