Upgrade xp-forge/yaml

Author: thekid

composer.json

@@ -16,7 +16,7 @@
     "xp-forge/rest-client": "^6.0",
     "xp-forge/handlebars-templates": "^4.0",
     "xp-forge/markdown": "^8.0",
-    "xp-forge/yaml": "^8.0",
+    "xp-forge/yaml": "^9.0",
     "xp-forge/hashing": "^3.0",
     "xp-forge/inject": "^6.0",
     "xp-forge/mongodb": "^3.0"