Update Riot to 1.5.13

Summary:
Update Riot to 1.5.13

Changelog available here

Test Plan: Used Riot to chat with friends for a couple of hours, including sharing images, links, etc.; made a short conference call

Reviewers: Triage Team, JoshStrobl

Reviewed By: Triage Team, JoshStrobl

Subscribers: JoshStrobl

Differential Revision: https://dev.getsol.us/D8507