dut_manager_test.py: Fix a lint error

Fix a lint error so that run_tests.sh proceeds to execute unit tests.
Currently, run_tests.sh aborts after running pylint because of the following lint error:

************* Module bisect_kit.dut_manager_test
bisect_kit/dut_manager_test.py:613:20: W0719: Raising too general exception: Exception (broad-exception-raised)

BUG=None
TEST=./run_tests.sh proceeds to run unittests after pylint

Change-Id: I8448f51576783f3a450c49cef23f735cb1e4ec0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/bisect-kit/+/5724253
Commit-Queue: Ryo Hashimoto <hashimoto@chromium.org>
Tested-by: Ryo Hashimoto <hashimoto@chromium.org>
Reviewed-by: Cheng-Yu Lee <cylee@google.com>
1 file changed