Only replace specific mongodb driver version

composer.json

@@ -15,7 +15,7 @@
         "phpunit/phpunit": "^4.8 || ^5.0"
     },
     "replace": {
-        "ext-mongo": "self.version"
+        "ext-mongo": "1.6.12"
     },
     "autoload": {
         "psr-4": {