doogfooding use String.join

Change-Id: If83b6421fc216aa54d3fd1edc9387b781d619861
Signed-off-by: Carsten Hammer <carsten.hammer@t-online.de>
Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.debug/+/174182
Tested-by: Platform Bot <platform-bot@eclipse.org>
Reviewed-by: Alexander Kurtakov <akurtako@redhat.com>
1 file changed