(elasticloadbalancingv2): cant set grpc code matcher on alb

[ChristopheBougere]

With #13570, it is now possible to set the protocol version for ALB target groups, and thus make it working for GRPC.
However, it is not yet possible to define a GrpcCode for the matcher (see CloudFormation doc).

Use Case

Being able to define a custom GRPC Code for the matcher, like for HTTP Code

Proposed Solution

Add a healthyGrpcCodes working the same way as healthyHttpCodes.

• 👋 I may be able to implement this feature request

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This is a 🚀 Feature Request

[github-actions]

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