How do I disable the notifications for the upgrade to macOS High Sierra?

I'm currently using macOS Sierra and my computer has a (what seems to be) daily notification to upgrade to macOS High Sierra. Does anyone know how to disable that "helpful" reminder as I do not intend to upgrade in the near term?

I don't remember prior upgrades being helped along by such a persistent notification, but that could just be me.

Thanks in advance for your help.