Iss2312 - Allow max gRPC message size to be set from Helm Chart value

[jadecarino]

Why?

For galasa-dev/projectmanagement#2312

Allow max gRPC message size to be set from Helm Chart value to avoid the error RESOURCE_EXHAUSTED: gRPC message exceeds maximum size.

Changes

• New optional parameter added to the values.yaml file to set a new maximum message size for a gRPC frame.
• Helper template to default this value if not provided, and also transform into an integer.
• Pass this new parameter in as an environment variable to all deployments so it can be used when setting up a client to talk to etcd3 with.