Part 4: Curl FFI; memory leak

[Horki]

Hi @rylev , example has a memory leak

DUMP

==1343581== HEAP SUMMARY:
==1343581==     in use at exit: 8,277 bytes in 21 blocks
==1343581==   total heap usage: 31,679 allocs, 31,658 frees, 2,979,697 bytes allocated
==1343581== 
==1343581== LEAK SUMMARY:
==1343581==    definitely lost: 0 bytes in 0 blocks
==1343581==    indirectly lost: 0 bytes in 0 blocks
==1343581==      possibly lost: 0 bytes in 0 blocks
==1343581==    still reachable: 8,277 bytes in 21 blocks
==1343581==         suppressed: 0 bytes in 0 blocks
==1343581== Rerun with --leak-check=full to see details of leaked memory
==1343581== 
==1343581== For lists of detected and suppressed errors, rerun with: -s
==1343581== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)