Fix adobe issue

.travis.yml

@@ -3,6 +3,7 @@ services:
 before_script:
   - echo "USE mysql;\nUPDATE user SET password=PASSWORD('dev') WHERE user='root';\nFLUSH PRIVILEGES;\n" | mysql -u root
 install:
+  - rm $TRAVIS_BUILD_DIR/tools/phpunit
   - composer require --dev phpunit/phpunit ^5.7
   - $TRAVIS_BUILD_DIR/vendor/bin/phpunit --version
   - cp $TRAVIS_BUILD_DIR/vendor/bin/phpunit $TRAVIS_BUILD_DIR/tools
@@ -12,4 +13,6 @@ language: php
 php:
   - '5.6'
   - '7.0'
+  - '7.1'
+  - 'nightly'
 after_failure: "cat /tmp/icehrm.test.log"