fix: proper relative path to protobufjs in cli (#1753)

According to https://docs.npmjs.com/cli/v8/configuring-npm/package-json#local-paths the local path should be `file:..` instead of `file://..`.

The later version copies whole top-level file-system in a macOS and with a recent version of npm (8.12.2) and results in a `MODULE_NOT_FOUND` error.

Co-authored-by: Alexander Fenster <fenster@google.com>

cli/package.json

@@ -30,6 +30,6 @@
     "uglify-js": "^3.7.7"
   },
   "devDependencies": {
-    "protobufjs": "file://.."
+    "protobufjs": "file:.."
   }
 }