run-robot: do not exit script on error

This script is running the robot test framework. Errors are expected
from the ROBOT_TEST_CMD at times when it finds regressions. Need to
ensure the script keeps running after that so it copies the needed log
files out of the docker container to the persistent directory.

Tested:
Verified that when robot tests fail we now get the test results and FFDC
in the jenkins job running it

Change-Id: Ieb87aba59402734837efb597aafd6dee434ce370
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/scripts/run-robot.sh b/scripts/run-robot.sh
index 56adb96..3d4e3d6 100755
--- a/scripts/run-robot.sh
+++ b/scripts/run-robot.sh
@@ -1,4 +1,4 @@
-#!/bin/bash -ex
+#!/bin/bash -x
 # Extract and run the OpenBMC robot test suite
 #
 # The robot test results will be copied to ${HOME}