Do not emit color codes when running run-jdwp-tests.sh with no terminal

Tell Vogar to suppress color-related control characters if the script
output is not to a terminal. This is to ease reading logs produced by
the ART Buildbot.

Bug: 130709497
Test: art/tools/run-jdwp-tests.sh --mode host | tee /tmp/log.txt
Test: art/tools/run-jdwp-tests.sh --mode host
Change-Id: I98d62b67ac3cdb48e2657d204befc1e3b17db2d4
1 file changed