Updates strophe.js version in lock file (Fixes package-lock version).

package-lock.json

       "dev": true
     },
     "strophe.js": {
-      "version": "github:jitsi/strophejs#d05254fb28f4bbe6df5f905358582db3a12ee04c"
+      "version": "github:jitsi/strophejs#1501521d305e405f4dea3f51a5473f504672a7b3"
     },
     "strophejs-plugin-disco": {
       "version": "0.0.2",