Dump a new autoloader when generating a Phar

[swissspidy]

This is related to the remaining failing Behat tests when code coverage is running.

Basically what happens in the wp-cli-bundle repo is that we include the autoloader once in generate-coverage.php, and then in the generated Phar the same autoloader is included again. That causes a fatal error because the same ComposerAutoloaderInit... class is declared twice.

This PR addresses this by temporarily changing the autoloader class suffix for that generated Phar. Requires otherwise using a hardcoded suffix (instead of the default content-hash). See wp-cli/wp-cli-bundle#764 for that.

Requires the PHP 7.2 bump, see wp-cli/wp-cli-bundle#760

See Slack discussion for additional context

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 13 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/Context/FeatureContext.php	0.00%	13 Missing ⚠️

📢 Thoughts on this report? Let us know!

[swissspidy]

@schlessera would love to hear especially your thoughts on this situation & solution.