Lint all Rust projects in pre-commit

Summary:
Resolves ENG-2314.

• Added a get_cargo_paths.js - it contains a helper function that looks for Cargo project directory for given .rs file path.
• Modified .lintstaged.js to collect a set of modified cargo projects and pass this list to rust_pre_commit.sh script.
• Modified rust_pre_commit.sh script to accept Cargo project paths as command line arguments.

This way, cargo fmt + cargo check is run once per modified cargo project.

Test Plan:

# do some changes in any .rs file e.g. in 2+ services/ projects
# lint should run once per cargo project
# it's best to do some incorrect formatting
git add .

# or git commit, command below runs only the hook, without commiting
lint-staged

# linter should fail on your formatting

Reviewers: varun, jon, ashoat

Reviewed By: varun, jon, ashoat

Subscribers: ashoat, tomek, atul

Differential Revision: https://phab.comm.dev/D6310