Changelod - Travis build agains PHP 8.0

Author: grogy

CHANGELOG.md

@@ -18,6 +18,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Updated PHPCS dependency from [@jrfnl](https://github.com/jrfnl).
 - Cleaned coding style from [@jrfnl](https://github.com/jrfnl).
 - Provide one true way to run the test suite [#37](https://github.com/php-parallel-lint/PHP-Parallel-Lint/pull/37) from [@mfn](https://github.com/mfn).
+- Travis: add build against PHP 8.0 and fix failing test [#41(https://github.com/php-parallel-lint/PHP-Parallel-Lint/pull/41) from [@jrfnl](https://github.com/jrfnl).
 
 ## [1.2.0] - 2020-04-04