[yarn] Bump clang-format to 1.7.0

Summary:
Downstream dependencies have issues surfaced by yarn audit

The repo doesn't have release notes (that I could find), but looking at the commits since 1.5.0 they're all bumping deps and messing with CI

Depends on D3858

Test Plan: CI

Reviewers: def-au1t, palys-swm, ashoat

Reviewed By: ashoat

Subscribers: ashoat, Adrian, karol-bisztyga, yayabosh

Differential Revision: https://phabricator.ashoat.com/D3859