Add new argument to select destination of HTML report

[jorgecoca]

Hi @kevmoo 👋

I was wondering if there's any special reason to not having an option to select where the HTML report is being generated. I think this would be great for CI/CD environments, so consumers could publish their results into an archive repository.

If you agree to this feature, I can start working on a pull request. Let me know.

Thanks!

[jorgecoca]

I could add a new action (so three in total, the existing print and open, and a new one called generate), and at least it could generate a new folder in the root project with the HTML report.

We do something similar here: https://github.com/bmw-tech/ozzie.flutter