revise adr to support ssh

[ericsciple]

Proposing adding SSH support. This will help for users scripting submodule checkout.

Will open a separate ADR for a first-class submodule input.

[peaceiris]

Does this proposal mean that we can also do git push with the SSH key? If yes, we can solve this problem: (Github action not triggering gh-pages upon push - GitHub Community Forum) without setting up a personal access token or SSH key by ourself.

Now, the GitHub Pages Actions provides the SSH key input option to avoid the problem. It is useful that the setting up SSH key is supported by actions/checkout.

Thank you.

[ericsciple]

@peaceiris yes the ssh key will be persisted so you can script authenticated git commands. Will be removed at the end of the job.

[ericsciple]

reviewed offline w/ @thechrisjohnson