Crates.io version of code will panic on newer rustc due to stricter uninit checks

[5225225]

Hi! As part of rust-lang/rust#99389 I'm going through crates that will panic as part of stricter uninit checks, and sputnikvm-(rlp,stateful) both look like they trigger the checks, but on the crates.io version only.

I can't reproduce them on master, so I assume older versions of the code used elastic-array that's now been removed? If so, releasing a new version will fix anyone who's using it as a dependency.