Alternative to Adding ForeignCc Rules in WORKSPACE

I'm a fresh newbie to bazel, and I'd like to build a cmake library within a bazel project. I noticed your [documentation](https://bazel-contrib.github.io/rules_foreign_cc/) mentions putting ForeignCc rules in the WORKSPACE file, but from the [ bazel documentation](https://bazel.build/concepts/build-ref), WORKSPACE is legacy.

Where should I put the rules with newer versions of bazel? Should your documentation be updated?

Start with the linked rules_foreign_cc documentation and Bazel's build-ref documentation, then identify where the current setup instructions live. Clarify the supported replacement for WORKSPACE-based configuration and update the documentation so users of newer Bazel versions have actionable instructions.

Written by the indexing model from the issue text.