Suggested Update to README Step 6

[summercody]

Hello! I have one recommended update -- GitHub stopped allowing password authentication through CLI's in 2020, so if you add a remote by just typing in the repo URL (step 6) and you don't already have a personal access token enabled, you'll hit an error when you try to deploy. You have to add the remote using the repository's SSH key instead (or have a PAT set up!).

[gitname]

Hi @summercody, thank you for reporting this!

Link to related PR from September: #111