Reactivate CamelEditorCheckOpeningInSpecialCasesIT deactivated due to webkit issue

2 tests are failing:

• https://fusesource-jenkins.rhev-ci-vms.eng.rdu2.redhat.com/view/Fuse%20Tooling/job/jbosstools-fuse_master/1035/testReport/org.fusesource.ide.camel.editor.integration/CamelEditorCheckOpeningInSpecialCasesIT/openFileWithoutContext/
• https://fusesource-jenkins.rhev-ci-vms.eng.rdu2.redhat.com/view/Fuse%20Tooling/job/jbosstools-fuse_master/1035/testReport/org.fusesource.ide.camel.editor.integration/CamelEditorCheckOpeningInSpecialCasesIT/openFileWithoutContextWhenOutlinePageOpened/

error message is:

No more handles because there is no underlying browser available.
Please ensure that WebKit with its GTK 3.x bindings is installed (WebKit2 API level is preferred). Additionally, please note that GTK4 does not currently have Browser support.

related issues:

• https://bugs.eclipse.org/bugs/show_bug.cgi?id=559918
• https://github.com/eclipse/reddeer/issues/2059

The 2 failign tests were deactivated to unblock master.
it is workign fine on Fedora 31.
We expect it to be working on RHEL 8 and broken on RHEL 7.x

webkit 1 support has been dropped: https://www.eclipse.org/eclipse/news/4.15/platform_isv.php#webkit1-removal

webkit versioning is very subtle...
webkitgtk > 2.5 = webKit2
webkit <= 2.5 = webkit 1

seems that webkit 2 is available for RHEL 8 but not for RHEL 7
https://access.redhat.com/downloads/content/webkit2gtk3/2.24.4-2.el8_1/x86_64/fd431d51/package
https://access.redhat.com/downloads/content/rhel---7/x86_64/2456/webkitgtk3/2.4.11-2.el7/x86_64/fd431d51/package

the better chance to reactivate it for now seems to upgrade to RHEL 8 the Jenkins slaves used on Fuse Ci.
Unfortunately this is not trivial. Attempt here https://github.com/jboss-fuse/fuseinfra/pull/7 (for people with rights).
Fuse 6.x requires Java 7 which is not available for RHEL 8.
if we provide both versions (quoting Zoran explaining it well):

we would end up with less nodes and a bit of a mess: Fuse 6.x job brings RHEL 7 node and that node takes up our quota for 4h and no other jobs are scheduled on it, or vice versa for RHEL 8 jobs (though more jobs can be scheduled on RHEL 8, so less of an impact)