chore(package.json): fix repository.url

- `npm pkg fix`

Author: chimurai

package.json

@@ -28,7 +28,7 @@
   },
   "repository": {
     "type": "git",
-    "url": "https://github.com/chimurai/http-proxy-middleware.git"
+    "url": "git+https://github.com/chimurai/http-proxy-middleware.git"
   },
   "keywords": [
     "reverse",