ftests: Add a test to validate systemd configurations

ftests: Add a test to validate systemd configurations

Add a test case to parse test different combination of valid and invalid
systemd configurations.

-----------------------------------------------------------------
Test Results:
        Run Date:                          Feb 05 08:33:41
        Passed:                                  1 test(s)
        Skipped:                                 0 test(s)
        Failed:                                  0 test(s)
-----------------------------------------------------------------
Timing Results:
        Test                                   Time (sec)
        -------------------------------------------------
        setup                                        0.00
        060-sudo-cgconfigparser-systemd.py           4.31
        teardown                                     0.00
        -------------------------------------------------
        Total Run Time                               4.31

Signed-off-by: Kamalesh Babulal <kamalesh.babulal@oracle.com>
Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>
(cherry picked from commit 0da586ec36e0f0a9bd918ea9d1afc6db20d80b65)