feat: support php 8.1

[shouze]

This is my 1st contribution to this project so I'm no sure I'm doing right:

1. Should I also add an entry in the changelog?
2. How does the publication into https://github.com/qossmic/deptrac-shim work?

[shouze]

Do you prefer instead

Suggested change

	"php": "^7.4.0 || 8.0.* || 8.1.*",
	"php": "^7.4.0 || ^8.0.0",

[patrickkusebauch]

This is my 1st contribution to this project so I'm no sure I'm doing right:

1. Should I also add an entry in the changelog?
2. How does the publication into https://github.com/qossmic/deptrac-shim work?

1. No need, this is done automatically upon release from all the commits since the last release.
2. @dbrumann takes care of that for each release, so you don't have to worry about it.

[dbrumann]

Thanks a lot.

[shouze]

@dbrumann looks like ci is failing at the moment 😢

• Unit tests: https://github.com/qossmic/deptrac/runs/3482866519?check_suite_focus=true → seems to require an higher phpunit version
• Build: https://github.com/qossmic/deptrac/runs/3482871941?check_suite_focus=true
• e2e: https://github.com/qossmic/deptrac/runs/3482871941?check_suite_focus=true

[dbrumann]

Yes, I forgot to run the tests first. Not a big deal, though. We can allow PHP 8.1 to fail for now and then fix the issues.

I will have a look at it later.

[shouze]

Yes, I forgot to run the tests first. Not a big deal, though. We can allow PHP 8.1 to fail for now and then fix the issues.

I will have a look at it later.

Almost good in #685 except 2 things:

1. I don't know why infection is now broken with php 7.4
2. Those warnings in phpunit, ain't easy to fix because this prophecy trait looks to be not included into phpunit.phar