UB fixed in smallvec >= 1.13.2

[gendx]

According to servo/rust-smallvec#343, the smallvec crate had undefined behavior in the Smallvec::insert() function in versions >= 1.8.1, <= 1.13.1 (servo/rust-smallvec#343 (comment)).

Given the number of downloads and crates depending on it, it's probably worth recording it in the advisory database.