findbugs: ignore: absolute pathname in test case

findbugs complain that the code is using absolute path in File object,
the FileServletTest is using it to test input path

findbugs reason:
DMI: Code contains a hard coded reference to an absolute pathname (DMI_HARDCODED_ABSOLUTE_FILENAME)

Change-Id: Ic14b42211fbae45408f78e1efeb148bd1b0dba45
Signed-off-by: Shahar Havivi <shavivi@redhat.com>