[dogfooding] Use String.join JDT cleanup in p2

The resulting code is much shorter.

Change-Id: I1b5e6a59b1cc236c273e8005c174ef6bdf393341
Signed-off-by: Lars Vogel <Lars.Vogel@vogella.com>
Reviewed-on: https://git.eclipse.org/r/c/equinox/rt.equinox.p2/+/179100
Tested-by: Equinox Bot <equinox-bot@eclipse.org>
1 file changed