Remove the php adapter - it is not required

Author: redthor

composer.json

@@ -16,8 +16,7 @@
         "php": "^7.1",
         "doctrine/mongodb": "^1.0",
         "symfony/console": "^2.7|^3.3|^4",
-        "symfony/yaml": "^2.7|^3.3|^4",
-        "alcaeus/mongo-php-adapter": "^1.0"
+        "symfony/yaml": "^2.7|^3.3|^4"
     },
     "require-dev": {
         "phpunit/phpunit": "^7.0",