try travis build dir

.travis.yml

@@ -19,5 +19,6 @@ before_script:
   - bash unit-tests/bin/install.sh woocommerce_test root '' localhost $WP_VERSION
 
 script:
+  - composer install
   - bash unit-tests/bin/phpunit.sh
   - bash unit-tests/bin/phpcs.sh

unit-tests/bin/phpunit.sh

@@ -1,10 +1,3 @@
 #!/usr/bin/env bash
-WORKING_DIR="$PWD"
-cd "$WP_CORE_DIR/wp-content/plugins/woocommerce-rest-api"
-ls
-composer install
-./vendor/bin/phpunit --version
-./vendor/bin/phpunit -c phpunit.xml
-TEST_RESULT=$?
-cd "$WORKING_DIR"
-exit $TEST_RESULT
+"$TRAVIS_BUILD_DIR"/vendor/bin/phpunit --version
+"$TRAVIS_BUILD_DIR"/vendor/bin/phpunit -c phpunit.xml $@