minor #1801 install PhpUnitBridge dependencies before running tests (xabbuh)

This PR was merged into the 2.3-dev branch.

Discussion
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install PhpUnitBridge dependencies before running tests

So the output will be folded by default by Travis CI and does not
clutter the tests' output.

Commits
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a166584 install PhpUnitBridge dependencies before running tests

Author: xabbuh

.travis.yml

@@ -33,6 +33,8 @@ before_install:
   - if [ "$DEPENDENCIES" != "" ]; then composer config minimum-stability $DEPENDENCIES; fi
   - if [ "$SYMFONY_LTS" != "" ]; then composer require --dev --no-update symfony/lts=$SYMFONY_LTS; fi
 
-install: composer update $COMPOSER_FLAGS --prefer-dist
+install:
+  - composer update $COMPOSER_FLAGS --prefer-dist
+  - ./phpunit install
 
 script: ./phpunit