We use GithubIntegration.get_access_token to authenticate and after upgrading we now get this response:
github.GithubException.GithubException: 401 {"message": "'Expiration time' claim ('exp') must be a numeric value representing the future time at which the assertion expires", "documentation_url": "https://docs.github.com/rest"}
Reverting to 1.57 solves the issue.