contint: install libsikuli-script-java for browser tests

Sikuli is a java application test to test input in web browsers. Going
to be used by QA to test VisualEditor. Luckily, the software has been
packaged for Debian/Ubuntu so it is really simple to install.

bug: 54393
Change-Id: I32e33f00899e77c9eb2bad88e73d718d99d9f8d9
Merge "contint: install libsikuli-script-java for browser tests" into production