Revert "Add missing testing dependencies"

This reverts commit 6ed35ad83c.

composer.json

@@ -44,9 +44,7 @@
         "barryvdh/laravel-ide-helper": "^2.6",
         "codedungeon/phpunit-result-printer": "0.25.1",
         "friendsofphp/php-cs-fixer": "^2.16.1",
-        "fzaninotto/faker": "^1.9.1",
         "laravel/dusk": "^5.11",
-        "mockery/mockery": "^1.0",
         "php-mock/php-mock-phpunit": "^2.6",
         "phpunit/phpunit": "^7"
     },