Update version of eclipse.jdt.ls

[svor]

Description

Need to update version of eclipse-jdt-ls to 0.30.0 in che-ls-jdt to avoid build failure.
[ERROR] Failed to resolve target definition /home/vsvydenko/.m2/repository/org/eclipse/jdt/ls/org.eclipse.jdt.ls.tp/0.27.0.20181114223651/org.eclipse.jdt.ls.tp-0.27.0.20181114223651.target: Failed to load p2 metadata repository from location http://download.eclipse.org/eclipse/updates/4.10-I-builds/: No repository found at http://download.eclipse.org/eclipse/updates/4.10-I-builds.

It depends on #12262

[tolusha]

/cc @tsmaeder

[tsmaeder]

The build failure is due to the fact that builds of jdt.ls are not repeatable: i.e. they depend (necessarily) on integration builds of dependencies that go away after a while.

[tsmaeder]

@tsmaeder testing

[tsmaeder]

@tsmaeder testing