First, read the actual ToS. That will spell it out.

Second, even if they kick you off the platform, what’s the loss? Git doesn’t depend on a single server by design. If you have to switch to a different provider, all you have to do is set up an empty repository on the new platform, change the repository’s remote, and push. If the goal is to learn how to use git, then managing the remotes should be a part of it.