I'd be surprised if they did. I really don't see a business reason for them doing so. They are clearly laser focused on enterprise, which means massively bespoked internal build systems and work flow. And they'll be competing against a lot of entrenched internal solutions.

GitLab and Atlassian have a pricing model for displacing existing systems and encouraging adoption, but I can't see GitHub following suit. GitHub looks to like they want to be the Apple in the Apple vs Android. Android has the largest user base but due to Apple's premium pricing, they have the largest profit.