Memory loss

```
==11334== 240,540 (117,840 direct, 122,700 indirect) bytes in 4,910 blocks are definitely lost in loss record 1,031 of 1,037
==11334== at 0x4C2BB7B: malloc (vg_replace_malloc.c:299)
==11334== by 0x2103EF: ::wait (in /home/ec2-user/target/release/main)
==11334== by 0x19E0FA: std::sys_common::backtrace::__rust_begin_short_backtrace (in /home/ec2-user/target/release/main)
==11334== by 0x19DE83: core::ops::function::FnOnce::call_once{{vtable-shim}} (in /home/ec2-user/target/release/main)
==11334== by 0x23F594: call_once<(), dyn core::ops::function::FnOnce<(), Output=()>, alloc::alloc::Global> (boxed.rs:1811)
==11334== by 0x23F594: call_once<(), alloc::boxed::Box, alloc::alloc::Global>, alloc::alloc::Global> (boxed.rs:1811)
==11334== by 0x23F594: std::sys::unix::thread::Thread::new::thread_start (thread.rs:108)
==11334== by 0x525D40A: start_thread (in /usr/lib64/libpthread-2.26.so)
==11334== by 0x5AA540E: clone (in /usr/lib64/libc-2.26.so)
```