ruff

4af3f43e - Added the command to run ruff using pkgx to the installation.md (#8955)

Added the command to run ruff using pkgx to the installation.md (#8955) ## Summary This PR adds the command to run ruff using [pkgx](https://pkgx.sh). <!-- What's the purpose of the change? What does it do, and why? --> It's just showing that ruff is supported in one more package manager. ## Test Plan You can run `pkgx ruff` if you have pkgx installed or run `sh <(curl https://pkgx.sh) +github.com/charliermarsh/ruff sh `