R1:1dd62f79cedb

Fix more "msort()" vs "msortv()" callsites

Summary:
See <https://discourse.phabricator-community.org/t/unhandled-exception-when-logging-in-with-mfa/2828>. The recent changes to turn `msort()` on a vector an error have smoked out a few more of these mistakes.

These cases do not meaningfully rely on sort stability so there's no real bug being fixed, but we'd still prefer `msortv()`.

Test Plan: Viewed MFA and External Account settings panels. Did a `git grep 'msort(' | grep -i vector` for any more obvious…