Set global env for Travis

Author: dmitry-ivanov

.travis.yml

@@ -5,13 +5,18 @@ php:
   - 7.4
   - 8.0
 
+env:
+  global:
+    - COMPOSER_MEMORY_LIMIT=-1
+    - XDEBUG_MODE=coverage
+
 cache:
   directories:
     - $HOME/.composer/cache
 
 install:
-  - COMPOSER_MEMORY_LIMIT=-1 travis_retry composer install --no-interaction --prefer-dist
-  - COMPOSER_MEMORY_LIMIT=-1 travis_retry composer require --no-interaction --prefer-dist --dev php-coveralls/php-coveralls
+  - travis_retry composer install --no-interaction --prefer-dist
+  - travis_retry composer require --no-interaction --prefer-dist --dev php-coveralls/php-coveralls
 
 script: vendor/bin/phpunit --verbose --coverage-clover build/logs/clover.xml