fix: configure renovate to pin yjs patch

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

renovate.json

@@ -128,6 +128,16 @@
       ],
       "datasourceTemplate": "node",
       "depNameTemplate": "node version in workflows"
+    },
+    {
+      "fileMatch": [
+        "package.json"
+      ],
+      "matchStrings": [
+        "yjs@(?:npm%3A)?(?<currentValue>[\\d\\.]+)"
+      ],
+      "datasourceTemplate": "npm",
+      "depNameTemplate": "yjs"
     }
   ]
 }