Missed part of task_group_exptensions unpreview (#668) (#731)
Missed part of task_group_exptensions unpreview (#668) (#731)

Signed-off-by: Anton Potapov <46a4e7c6e329e26e2944dd3051648ee305c41419@intel.com>
oneapi-src/oneTBB,oneapi-src/oneTBB,oneapi-src/oneTBB,oneapi-src/oneTBB