Documentation refers to env variable with dot in the name GITHUB.BASE_URL

[pgrabowski]

Git provider

Github Enterprise

System Info

N/A

Bug details

Most shells don't support dot inside env variables name (https://unix.stackexchange.com/questions/93532/exporting-a-variable-with-dot-in-it)
Consider renaming all env variables with dot like GITHUB.BASE_URL

[IsmaelMartinez]

I opened PR #2439 to switch the documented environment-variable examples to the double-underscore form so they work in shells and GitHub Actions env blocks where the dotted form does not. I hope it helps, and do let me know if it needs any changes.