feat(test_vector_handlers): Hierarchy keyring test vectors

[lucasmcdonald3]

Issue #, if available:

Description of changes:

Support hierarchy keyrings in test vector manifests.

(Code to generate decrypt-generate manifests lives in https://github.com/awslabs/aws-crypto-tools-test-vector-framework/pull/36).

Testing

• Generate test vectors for the manifest in Code to generate decrypt-generate manifests lives in https://github.com/awslabs/aws-crypto-tools-test-vector-framework/pull/36
• Decrypt generated vectors with keyrings and master keys
• Decrypt generated vectors with .NET ESDK

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