ci: introduce helper to preserve select env variables under sudo

Change-Id: I0217b8fbb005a43dddaf0010aa85130411d20813
Refs: #4610
diff --git a/.jenkins.d/20-tests.sh b/.jenkins.d/20-tests.sh
index 00df3e5..ec4461b 100755
--- a/.jenkins.d/20-tests.sh
+++ b/.jenkins.d/20-tests.sh
@@ -40,5 +40,8 @@
 ASAN_OPTIONS+=":strip_path_prefix=${PWD}/"
 export ASAN_OPTIONS
 
+export BOOST_TEST_BUILD_INFO=1
+export BOOST_TEST_COLOR_OUTPUT=1
+
 # Run unit tests
 ./build/unit-tests $(ut_log_args)