Make Maven Fmt/ Lint Job Run Faster

[lqiu96]

From a recent run of the lint job (https://github.com/googleapis/google-cloud-java/actions/runs/15201184035/job/42755490835) took ~30 minutes to run.

Can we make this run faster?

Job details (

google-cloud-java/.github/workflows/ci.yaml

Line 82 in 80a9d63

- run: mvn -B -ntp com.spotify.fmt:fmt-maven-plugin:check -T 1C

) looks to try and run this in parallel.

Additional options to explore:

• Can we only fmt this on modules that have code changes instead of running this for the entire repo?
• Can we only fmt on PRs that have code changes (exclude CI or deps upgrades)?
• Does the fmt plugin to help speed this up natively? Some configurations that we can play around with?