Provide path for phpcs executable

ahoy.test.yml

 ahoyapi: v2
 commands:
   phpcs:
-    cmd: ahoy d4d exec phpcs --standard=DrupalPractice /var/www/html/web/modules/custom/ /var/www/html/web/profiles/custom/ /var/www/html/web/themes/custom/
+    cmd: ahoy d4d exec vendor/bin/phpcs --standard=DrupalPractice /var/www/html/web/modules/custom/ /var/www/html/web/profiles/custom/ /var/www/html/web/themes/custom/
     usage: PHP coding standards
   phpunit:
     cmd: ahoy d4d exec vendor/bin/phpunit --configuration /var/www/html/tests/phpunit.xml.dist