Cannot add ZIP as Project

[chris-aeviator]

Description

When adding a ZIP as a project to a workspace,Che will raise the following error

Couldnt clone http://code.oi.myserver.io:8888/my-project.zip: Request clone failed with message: Cloning into '/projects/my-project'...
fatal: unable to access 'http://code.oi.myserver.io:8888/my-project.zip/': The requested URL returned error: 500

Che seems to try to download the ZIP file with a trailing slash, which returns in the 500.

In my config I can see the url without the slash:

  "projects": [
    {
      "description": "",
      "source": {
        "location": "http://code.oi.myserver.io:8888/my-project.zip",
        "type": "zip",
        "parameters": {
          "skipFirstLevel": "false"
        }
      },
      "links": [],
      "problems": [],
      "mixins": [],
      "name": "my-project",
      "path": "/projects/my-project",
      "attributes": {}
    },

Reproduction Steps

 docker run -it --rm -v /var/run/docker.sock:/var/run/docker.sock -v /srv/dev.icm.myserver.io/:/data eclipse/che start

2. Start simple-theia-docker workspace
3. add zip file as project

OS and version:
Ubuntu 16.04
Docker version 18.06.1-ce, build e68fc7a

Diagnostics:

[vzhukovs]

Issue can't be reproduced. If there are any question, feel free to re-open the issue.