Removed hard phpunit dependency

.travis.yml

@@ -41,6 +41,7 @@ matrix:
 install:
  - wget "http://cs.sensiolabs.org/download/php-cs-fixer-v2.phar" --output-document="${HOME}/bin/php-cs-fixer" && chmod u+x "${HOME}/bin/php-cs-fixer"
  - wget "https://github.com/php-coveralls/php-coveralls/releases/download/v2.0.0/php-coveralls.phar" --output-document="${HOME}/bin/php-coveralls" && chmod u+x "${HOME}/bin/php-coveralls"
+ - wget "https://phar.phpunit.de/phpunit-5.7.phar" --output-document="${HOME}/bin/phpunit" && chmod u+x "${HOME}/bin/phpunit"
  - if [ "$SYMFONY_VERSION" != "" ]; then composer require "symfony/symfony:${SYMFONY_VERSION}" --no-update; fi;
  - if [ "$TARGET" == "lint" ]; then gem install yaml-lint && composer global require --dev sllh/composer-lint --no-update; fi
  - if [ "$TARGET" == "phpstan" ]; then composer global require --dev phpstan/phpstan:^0.9 --no-update; fi

composer.json

@@ -34,8 +34,6 @@
   "require-dev": {
     "matthiasnoback/symfony-dependency-injection-test": "^1.1",
     "php-http/mock-client": "^0.3",
-    "phpunit/phpunit": "^5.7",
-    "sebastian/exporter": "^2.0",
     "sonata-project/admin-bundle": "^3.1",
     "symfony/phpunit-bridge": "^4.0"
   },