add 'ws' back as dependency.

Author: endel

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "colyseus.js",
-  "version": "0.15.12",
+  "version": "0.15.13",
   "description": "Colyseus Multiplayer SDK for JavaScript/TypeScript",
   "author": "Endel Dreyer",
   "license": "MIT",
@@ -60,7 +60,8 @@
   "dependencies": {
     "@colyseus/schema": "^2.0.4",
     "httpie": "^2.0.0-next.13",
-    "tslib": "^2.1.0"
+    "tslib": "^2.1.0",
+    "ws": "^8.13.0"
   },
   "devDependencies": {
     "@rollup/plugin-alias": "^3.1.2",
@@ -83,7 +84,6 @@
     "ts-loader": "^6.2.1",
     "ts-node": "^6.0.3",
     "tslint": "^5.9.1",
-    "typescript": "^4.3.5",
-    "ws": "^7.4.3"
+    "typescript": "^4.3.5"
   }
 }