Update Riot to 1.5.12
Summary:
Update Riot to 1.5.12
Changes:
- Upgrade to React SDK 2.2.1
- Revert to Electron 7.1.12 to fix tray icon
Test Plan: Chatted with my friends, sent an image, made a short conference call
Reviewers: Triage Team, JoshStrobl
Reviewed By: Triage Team, JoshStrobl
Subscribers: JoshStrobl
Differential Revision: https://dev.getsol.us/D8428