tests: kernel: work_q: Add testcases

Add a testcase where single work is submitted to
multiple queue. In this case handler invoked only
once as single work cannot be submitted to multiple
queue.

Add a test case which submit a work to a queue twice. This testcase
is added to test neagtive case when  k_delayed_work_cancel() fails
in k_delayed_work_submit_to_queue API

Signed-off-by: Savinay Dharmappa <savinay.dharmappa@intel.com>