[services] fix rust-pre-commit hook

Summary: we add the "all" flag to format all packages and their local dependencies. we add the "check" option to run rustfmt in check mode, which ensures that the pre-commit hook fails further formatting is required.

Test Plan: tried unformatting some code in the commtest package and then committing my changes. the linter stopped me from committing the code, as expected

Reviewers: karol-bisztyga, palys-swm, jimpo

Reviewed By: palys-swm

Subscribers: ashoat, Adrian, atul, yayabosh

Differential Revision: https://phab.comm.dev/D4423