task_group extensions : task_handle comparison operators unit tests (#451)
task_group extensions : task_handle comparison operators unit tests (#451)

* task_group extensions

- unit tests for empty check / comparison operators

Signed-off-by: Anton Potapov <46a4e7c6e329e26e2944dd3051648ee305c41419@intel.com>

Co-authored-by: Aleksei Fedotov <15108d320a612097f2e47b5601489a61a302ec8f@intel.com>
oneapi-src/oneTBB,oneapi-src/oneTBB,oneapi-src/oneTBB,oneapi-src/oneTBB