[Travis] Unlimited memory for composer update

Author: Naktibalda

.travis.yml

@@ -20,7 +20,7 @@ sudo: false
 install:
   - '[[ -z "$CI_USER_TOKEN" ]] || composer config github-oauth.github.com ${CI_USER_TOKEN};'
   - travis_retry composer self-update && composer --version
-  - travis_retry composer update --prefer-dist --no-interaction
+  - COMPOSER_MEMORY_LIMIT=-1 composer update --prefer-dist --no-interaction
 
 before_script:
   - 'mysql -e "create database codeception_test;"'