Document process for pre-releases

[masteradhoc]

We should document the proper way how to do pre-releases/betas for two-factor.

[jeffpaul]

I believe you can still use the pre-release checkbox in the GitHub releases flow, then adjust what's used in the deploy action here

two-factor/.github/workflows/deploy.yml

Line 5 in 258e11b

types: [published]

and instead of published there's released(see https://docs.github.com/en/actions/reference/workflows-and-actions/events-that-trigger-workflows#release for more)