ci.jpl: Quote boot/test output in a failure message

Such output may itself contain colon, as the failure message itself, which
makes hard to parse it and figure out which is which.

Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Change-Id: I419544155ee4142ea5e9722889c25e2b4c5efce8
1 file changed