Implement DetermineVerisons()

[t-kikuc]

They should be supported for ecspresso, ecschedule, lambroll

e.g.

pipecd-plugin-prototypes/plugins/lambroll/deployment/server.go

Lines 95 to 100 in 3964181

	// DetermineVersions implements deployment.DeploymentServiceServer.
	func (s *DeploymentServiceServer) DetermineVersions(ctx context.Context, request *deployment.DetermineVersionsRequest) (*deployment.DetermineVersionsResponse, error) {
	return &deployment.DetermineVersionsResponse{
	Versions: nil,
	}, nil
	}