randlanet_url is not accesible [seems that again]

### Checklist

- [X] I have searched for [similar issues](https://github.com/isl-org/Open3D-ML/issues).
- [X] I have tested with the [latest development wheel](http://www.open3d.org/docs/latest/getting_started.html#development-version-pip).
- [X] I have checked the [release documentation](http://www.open3d.org/docs/release/) and the [latest documentation](http://www.open3d.org/docs/latest/) (for `master` branch).

### My Question

In one of the examples, there is pth file for randlanet
```
https://storage.googleapis.com/open3d-releases/model-zoo/randlanet_semantickitti_202009090354utc.pth"
```
but it seems that a file is not there, on the cloud. Can you tell me where I could find it, because it seems that in Zoo-models proposals, there is the same file.

Or maybe you need to change the permission access to the file?