[CI] fix jbosstools-install-p2director build

The CI build that checks that from a base eclipse, all component provided by JBossTools can be installed [1] fails since NodeClipse update site intagrated a new release of EGit.

JBosstools update repository contains EGit release from 2019-09 and NodeClipse contains a newer release.

The reason is that p2director cannot do updates of already installed features, neither be able to reconcile the installation of two different versions of the same feature.

[1] https://dev-platform-jenkins.rhev-ci-vms.eng.rdu2.redhat.com/view/Devstudio/view/devstudio_master/job/jbosstools-install-p2director.install-tests.matrix_master/