Update .travis.yml in order to require "symfony/translation" in a specific version

Author: phansys

.travis.yml

@@ -37,7 +37,7 @@ cache:
 
 before_install:
   - rm -rf composer.lock vendor/
-  - if [ "$SYMFONY_VERSION" != "" ]; then composer require "symfony/workflow:${SYMFONY_VERSION}" --no-update; fi;
+  - if [ "$SYMFONY_VERSION" != "" ]; then composer require "symfony/workflow:${SYMFONY_VERSION}" "symfony/translation:${SYMFONY_VERSION}" --no-update; fi;
 
 install: COMPOSER_MEMORY_LIMIT=-1 travis_retry composer install --prefer-dist --no-interaction