func WithProject(project string) Option {
	return func(opts *Options) {
		opts.project = project
	}
}
WithProject configures the Pubsub client with the named project.
package gcp
type Options struct {
	project          string
	topic            string
	topicDone        string
	subscription     string
	subscriptionDone string
	tokenpath        string
}
type Option func(*Options)