Did you even read the email? It's an extremely boring standard billing notification that explains exactly why that person received it "You're receiving this because your organization is using the GitHub Code Quality public preview." and when it would be come into affect.

It's not a small print somewhere, or one of these weekly app store subscriptions that run up high bills because someone clicked "Yes" in a game.

It's like calling a Netflix renewal email a "shakedown" just because they send you an email giving you a heads up that your trial will convert into a paid subscription.