This is similar to gb_JunitTest_DEBUGRUN, i.e. allows running soffice in
gdb, and then connecting to that soffice from the test, instead of
starting an own one.

Change-Id: I023d6b0ede146837666c946cb865feb9046e5a94
Reviewed-on: https://gerrit.libreoffice.org/42756Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>