[2.0, UI] There's no spacing between combo boxes under the Machine Details page

[Andres Rodriguez]

[Description]

When trying to deploy a machine, there's no spacing between combo boxes.

[Steps to reproduce]
1. Go the Nodes tab
2. Select a machine and click on a machine toa ccess Machine Details page.
3. Select 'Deploy' from the menu
4. you will see https://people.canonical.com/~andreserl/maas-rc1-deploy-on-node-details.png

Once you click deploy, the options/combo boxes will appear to select OS, Release, kernel. As you can see in https://people.canonical.com/~andreserl/maas-rc1-deploy-on-node-details.png , there's no spaces. To compare you can do the same from the details page.