@Bean
    // Create credentials for username + password.
    CallCredentials grpcCredentials() {
        return CallCredentialsHelper.basicAuth(this.username, this.username + "Password");
    }
The security configuration for the client. In this case we assume that we use the same passwords for all stubs. If
you need per stub credentials you can delete the grpcCredentials and define a {@link StubTransformer} yourself.

@author Daniel Theuke (daniel.theuke@heuboe.de)
@see CallCredentialsHelper
examples/security-grpc-client/src/main/java/net/devh/boot/grpc/examples/security/client/SecurityConfiguration.java