Unsoundness in ninjabook

[lwz23]

see ninja-quant/ninjabook#3 for detail.
Description
The get_mutand get function in the Orderbook implementation uses unsafe code to call Buffer::get_unchecked_mut, bypassing bounds checking. This function is unsound because it allows access to an arbitrary index without ensuring that the index is within bounds. If the caller provides an out-of-bounds index, the program will invoke undefined behavior (UB).

author didn't reply yet, so no patched version.