kunit: tool: add missing test data file content

Add a missing raw dmesg test log to test the kunit_tool's dmesg parser.
test_prefix_poundsign and test_output_with_prefix_isolated_correctly
fail without this test log.

Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>