[CI] add error-prone scan so we are less likely to break the upstream bazel CI

[luxe]

An unreleased version of bazel saw errors while running buildfarm tests. They use google/error-prone and we should mimic that downstream and avoid future issues. See recent fix: https://github.com/bazelbuild/bazel-buildfarm/pull/744

bazel out of the box: https://errorprone.info/docs/installation