Ask users to choose a pronoun instead of sex in the Account settings panel
Summary: Fixes T4845, Use "choose a pronoun" prompt for (grammatical) gender selection instead of "Sex"
Test Plan: Open Account settings panel, expand Pronoun dropdown, verify that options are "<username> updated their/her/his profile". Switch to different language, verify that pronouns propogate
Reviewers: epriestley, #blessed_reviewers
Reviewed By: epriestley, #blessed_reviewers
Subscribers: epriestley, Korvin
Maniphest Tasks: T4845
Differential Revision: https://secure.phabricator.com/D8920