Jarosław Stachowiak

I also created a similar issue but for a slightly different scenario in #6597.

In my case, `github_app_token` was mutating the provider client's `BaseURL` in-place. If you didn't allocate it, don't mutate it. https://github.com/integrations/terraform-provider-github/blob/a3b39ede0d4a813b81ed93413c07d8ac58343743/github/apps.go#L41 https://github.com/integrations/terraform-provider-github/pull/2951