ftests: Add cgroup_get_current_controller_path() (v2) test

ftests: Add cgroup_get_current_controller_path() (v2) test

Add a test cases to stress pybindings of get_current_controller_path(),
that calls cgroup_get_current_controller_path() on unified mode.

-----------------------------------------------------------------
Test Results:
        Run Date:                          Apr 27 11:21:33
        Passed:                                  1 test(s)
        Skipped:                                 0 test(s)
        Failed:                                  0 test(s)
-----------------------------------------------------------------
Timing Results:
        Test                                             Time (sec)
        -----------------------------------------------------------
        setup                                                  0.00
        082-pybindings-cgrp_get_curr_ctrl_path-v2.py           2.18
        teardown                                               0.00
        -----------------------------------------------------------
        Total Run Time                                         2.18

Signed-off-by: Kamalesh Babulal <kamalesh.babulal@oracle.com>
Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>