Follow up from wasmtime: Check reasonable sizes for fixed-size-lists in validator

[cpetig]

Hm ok I agree that this doesn't need to be fallible, but we should probably add a reasonable size limits in wasm-tools as well, e.g. 1G or something like that, to ensure that calculations don't overflow

Originally posted by @alexcrichton in bytecodealliance/wasmtime#10619 (comment)