Remove the repository containing GEF FX from the targlet in the setup

The set of IUs between GEF FX and GEF Classic are not unique, so more
care must be taken to avoid resolving the GEF FX IUs with higher version
into the target platform.  Furthermore, GEF Classic does not even
require an Orbit repo to resolve the target platform; purely the
Platform SDK is sufficient.

#352

setup/GEF.setup

@@ -200,8 +200,6 @@
           rootFolder="${git.clone.gef.classic.location}"
           locateNestedProjects="true"/>
       <repositoryList>
-        <repository
-            url="https://download.eclipse.org/releases/${eclipse.target.platform.latest}"/>
         <repository
             url="https://download.eclipse.org/cbi/updates/license"/>
       </repositoryList>