EvcBundle

Downgrading to phpunit8 to be compliant with PHP7.2

Removing symfony-bridge because it install phpunit6.5 on symfony 3.4 and I use methods from phpunit8

Removing symfony-bridge because it install phpunit6.5 on symfony 3.4 and I use methods from phpunit9

minor [#13001](https://github.com/symfony/symfony-docs/pull/13001) composer issue for prefer-lowest has been fixed

Merge remote-tracking branch 'origin/master'