Close #760, use dainstall so PRs can test too

[plocket]

In this PR, I have:

• [x] Added tests for any new features or bug fixes (if relevant)
• [x] Added my changes to the CHANGELOG.md at the top, under the "Unreleased" section
• [x] Ensured issues that this PR closes will be automatically closed

Reason for this PR

Allow alkiln to test PRs and such as well. Use our own action to avoid having to update all the time

Links to any solved or related issues

Close #760, close #822

Any manual testing I have done to ensure my PR is working

Command line experiments with dainstall and such.

Notes

Until/unless the PR in docassemblecli is accepted, local development is going to take a bit more setup work and we'll have to update our own README docs.

[Also, I found something somewhere that said that one of our commands (not sure which one) wasn't going to work on windows. Or maybe something in dainstall? I'm not sure what doesn't work or where I found the info. Maybe that problematic code is gone. We need to try the dainstall flow on a windows computer, though.]