New creates a new instance of the Fixture.

CA is the certificate authority.

CAKey is the private key of the certificate authority.

ClientTLS is a set of transport credentials to use with chains signed by `CA`.

Localhost is a certificate for "localhost" signed by `CA`.

RootCAs is a certificate pool containing `CA`.

Fixture encapsulates the TestService gRPC server, a proxy and a gRPC client.

Server is a testing gRPC server.