Update .travis.yml

Author: TheTechsTech

.travis.yml

@@ -16,7 +16,7 @@ services:
 
 # Commands to be run before your environment runs.
 before_script:
-  - composer self-update
+  - composer install --no-interaction --no-progress --prefer-dist
 #  - composer require phpstan/phpstan "0.11.3"
   - mysql -e 'CREATE DATABASE IF NOT EXISTS ez_test;'
   - mysql -e "CREATE USER ez_test@localhost IDENTIFIED BY 'ezTest'; GRANT ALL ON ez_test.* TO ez_test@localhost; FLUSH PRIVILEGES;"