FatalErrorException with PHPUnit 8.4.3 and PHP 7.3

[weisswurstkanone]

The signature obviously has changed. See sebastianbergmann/phpunit@f5e5add

Fatal error: Declaration of Cache\IntegrationTests\CachePoolTest::setUp() must be compatible with PHPUnit\Framework\TestCase::setUp(): void in /home/travis/build/pimcore/pimcore/vendor/cache/integration-tests/src/CachePoolTest.php on line 896
In CachePoolTest.php line 896:

[Symfony\Component\Debug\Exception\FatalErrorException]
Compile Error: Declaration of Cache\IntegrationTests\CachePoolTest::setUp()
must be compatible with PHPUnit\Framework\TestCase::setUp(): void