fix: remove references to @rules_cc//cc:defs.bzl

[comius]

Referring to @rules_cc//cc:defs.bzl, refers to @protobuf//bazel:cc_proto_library.bzl, which fetches protobuf repository.
Referring directly to what's needed limits the fetches just to rules_cc.

Fix reference to bzl libs in rules_cc that are needed for docs generation.

[meteorcloudy]

I don't see any reason the RBE jobs have to build with Bazel 6.4.0 and ubuntu1604, please upgrade to Bazel 7.3.2 and ubuntu2204

[rickeylev]

We still support Bazel 6, so we should have an RBE for that. Do you mean for the Bazel 7 RBE job? It looks like its using 7.1 (which is a bit surprising; I thought our CI was setup to use 7.x, i.e. latest 7)

[meteorcloudy]

I'm not sure which one is the Bazel 7 RBE job, but the for those RBE jobs, you should upgrade to rbe_ubuntu2004.

If Bazel 6 is still supported, then we need to fix rules_cc, sent bazelbuild/rules_cc#253

[aignas]

FYI, once bazel 8 is out, we will start removing support for bazel 6, but if we can maintain compatibility in an easy way that wouldn't hurt. As for bazel version, we are defining it in .bazelversion in the rules_python repo, maybe we should remove that file to instead test with the latest available stable version?