No pom.xml in gerrit-plugin-gwtui to update

9a13f852f04b956f1d8b51526732d187258ef58b add utility script to update
pom.xml with newest version.  gerrit-plugin-gwtui project doesn't have
pom.xml and must not be updated.

Change-Id: If2d367e8b8c0a5c4960bfc0a059b42cf951e7462
(cherry picked from commit c092bc24fefce072079ea8af58ef7f5c35236c67)