Fix for Composer installation

[kubawerlos]

When humbug/box is installed via Composer then

require_once __DIR__.'/../vendor/composer/InstalledVersions.php';

(from https://github.com/box-project/box/blob/4.0.2/src/functions.php#L61)

fails as this files exist only when is used as PHAR.

Current behaviour can be seen in the failing check in PHP-CS-Fixer/PHP-CS-Fixer#6554.

[igorkgg]

+1

[Zegnat]

In waiting for this PR, I have been able to apply it through cweagans/composer-patches. Installation instructions from scratch:

composer config --no-plugins allow-plugins.bamarni/composer-bin-plugin true
composer require --dev bamarni/composer-bin-plugin
composer bin box config allow-plugins.cweagans/composer-patches true
composer bin box require --dev cweagans/composer-patches
composer bin box config --json extra.patches '{ "humbug/box": { "Fix for Composer installation": "https://github.com/box-project/box/pull/695.patch" } }'
composer bin box require --dev humbug/box

[theofidry]

Thank you very much @kubawerlos!