update travis

Author: nasrulhazim

.travis.yml

@@ -7,7 +7,8 @@ php:
 
 before_script:
   - travis_retry composer self-update
-  - travis_retry composer update --prefer-source --no-interaction --dev
+  - travis_retry composer install
 
 script:
+  - composer dumpautoload -o
   - vendor/bin/phpunit