Split CS and PHPStan steps in Travis build

Author: Jean85

.travis.yml

@@ -35,7 +35,9 @@ jobs:
       script:
         - composer require --dev phpstan/phpstan symfony/expression-language --no-interaction --prefer-dist --prefer-stable
         - vendor/bin/phpstan analyse src --level 7
-        - vendor/bin/php-cs-fixer fix --verbose --diff --dry-run
+      env: PHPSTAN=true
+    - script: vendor/bin/php-cs-fixer fix --verbose --diff --dry-run
+      env: CS-FIXER=true
     - stage: coverage
       php: 7.1
       script: