[services] Add electron update server to the services

Summary: Adds the electron update server to the services. It's using the hazel package.

Test Plan:
Run yarn dev and yarn prod (with env vars pointing at a custom repo) and check if it correctly serves files. Example:
HAZEL_ACCOUNT=MichalGniadek HAZEL_REPOSITORY=comm-test-gh HAZEL_PORT=3005 yarn dev will use this repo: https://github.com/MichalGniadek/comm-test-gh that already has some releases with necessary files created.

Reviewers: atul, jon, varun, ashoat

Reviewed By: ashoat

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D6353