downgrade php version

Author: rustagir

composer.json

@@ -2,7 +2,7 @@
   "name": "mongodb/docs-php-library",
   "description": "MongoDB PHP Library Documentation",
   "require": {
-    "mongodb/mongodb": "^1.20"
+    "mongodb/mongodb": "^1.19"
   },
   "require-dev": {
     "doctrine/coding-standard": "^12.0",