Long-living PHP support (Swoole/RoadRunner etc)

@demyr

1. Now I don't create any new package or something new.
2. I would like to support Long-living PHP officially in the future, but it is still a long way off.
3. I contributed Codeigniter4-Roadrunner, and https://github.com/monkenWu/CodeIgniter4-Burner is the next project of the creator of Codeigniter4-Roadrunner. So I recommend all of you see the package if you have interested in this topic.

First, currently there is no consensus to support or try to support Long-living PHP, so it would be nice that we would have that.
Second, if there is something wrong with CI4 code to work with them, I would like to fix it. So I want to know exact issues.
Then I would like to modify CI4 so that packages like CodeIgniter4-Burner work with less code.

ci-phpunit-test | CodeIgniter Testing Guide | CodeIgniter 3 to 4 Upgrade Helper