Memory leak in async.cpp about measurement-kit HOT 2 CLOSED

==1794== 
==1794== HEAP SUMMARY:
==1794==     in use at exit: 120 bytes in 3 blocks
==1794==   total heap usage: 330,569 allocs, 330,566 frees, 37,104,432 bytes allocated
==1794== 
==1794== LEAK SUMMARY:
==1794==    definitely lost: 0 bytes in 0 blocks
==1794==    indirectly lost: 0 bytes in 0 blocks
==1794==      possibly lost: 0 bytes in 0 blocks
==1794==    still reachable: 120 bytes in 3 blocks
==1794==         suppressed: 0 bytes in 0 blocks
==1794== Rerun with --leak-check=full to see details of leaked memory
==1794== 
==1794== For counts of detected and suppressed errors, rerun with: -v
==1794== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)