1058231: Adjusted "last update" label positioning

- Moved the "Last Update" label on the SubMan GUI "view facts"
  dialog such that it now sits on a line above the actual date.
  This should provide extra space for displaying the date in
  certain languages without significantly changing the layout.
Merge pull request #1093 from candlepin/crog/1058231

1058231: Adjusted "last update" label positioning