Support php8 by removing safe library (#39)

* Add PHP8 to PHP matrix

* Update Phan to ^4.0 for PHP8 support

* Update PHPUnit to latest version for code coverage to work with PHP8

* Re-implement Safe methods and ignore them in code coverage, strenghten CI runs with PHPUnit and Infection and make sure 100% is minimum requirement

* Run PHPUnit and Infection in one go so XML files are available to Infection

* Inline Exceptions and remove static method and update PHP-CS-Fixer

Show PHP version in GitHub Action job (#38)

* Show PHP version in GitHub Action job

* Libraries does not containt a .lock file

* Fix linter name

Use matrix suite variable in task name (#37)

Us the `${{ matrix.suite }}` variable in the name of the task

Do not rely on third party images to build our image (#32)

* Do not rely on third party images to build our image

* `PHLAK\Config\Config` cannot resolve phar paths and fails

```
Warning: include(): Filename cannot be empty in phar:///usr/bin/converter/vendor/phlak/config/src/Loaders/Php.php on line 19

Warning: include(): Failed opening '' for inclusion (include_path='.:/usr/local/lib/php') in phar:///usr/bin/converter/vendor/phlak/config/src/Loaders/Php.php on line 19

Fatal error: Uncaught PHLAK\Config\Exceptions\InvalidFileException:  does not return a valid array in phar:///usr/bin/converter/vendor/phlak/config/src/Loaders/Php.php:22
Stack trace:
  thrown in phar:///usr/bin/converter/vendor/phlak/config/src/Loaders/Php.php on line 22
```

Using include, we can get the evalatued content from a php file, in that case an
array, and use it as a constructor argument.

Add option to fail with non-zero exit code when there are more than 0…

… errors in order to fail pipelines (#27)

Closes beechit/json-to-code-climate-subset-converter#19

Update README.md: Add PHP-CS-Fixer (#26)

Add Infection Action (#24)

* Update composer.json: add Infection script

* Create infection.yml GitHub Action

* Update README.md: Add Infection badge

* Add infetion.json.dist

* Add XDEBUG_MODE=coverage to infection-ci script in composer.json

* Run infection-ci task from GitHub Action

Remove php 7.2 (EOL)

Update GH Actions by removing php 7.2 from the matrix. Also update composer.json to 7.3 minimum.

Merge pull request #20 from beechit/ttomdewit-patch-1

Update converter: Check one level deeper to find autoload file.

Update README.md

Remove most of README since we have dedicated WIKI entries