listen to ydoc destroy event

package.json

@@ -68,7 +68,7 @@
     "yjs": "^13.2.0"
   },
   "peerDependenies": {
-    "yjs": "^13.0.0"
+    "yjs": "^13.4.6"
   },
   "optionalDependencies": {
     "ws": "^7.2.0"

src/y-webrtc.js

@@ -582,6 +582,8 @@ export class WebrtcProvider extends Observable {
       }
     })
     this.connect()
+    this.destroy = this.destroy.bind(this)
+    doc.on('destroy', this.destroy)
   }
 
   /**
@@ -618,6 +620,7 @@ export class WebrtcProvider extends Observable {
   }
 
   destroy () {
+    this.doc.off('destroy', this.destroy)
     // need to wait for key before deleting room
     this.key.then(() => {
       /** @type {Room} */ (this.room).destroy()