Workaround for Bug 1262

Disable the build of light-ui until it can be updated with a newer
version of Ubuntu, Python 3 and NPM.

Change-Id: I6ed11216c4ba71fd784c113342d49bd941349fd3
Signed-off-by: beierlm <mark.beierl@canonical.com>
(cherry picked from commit c3a33005)