[wheel] limit build artifacts duplicated in example directory for ray_cpp (#54465)

## Why are these changes needed?

Currently, the built wheels include the `ray/cpp/example/`, which
includes a total copy of the `lib` and `include` directories (because
they are copied here in `//cpp:ray_cpp_pkg`. This just about doubles the
size of the wheels being distributed right now (~35MB for `include` and
~35MB for `lib`)

This change modified the `//cpp:ray_cpp_pkg` target to not copy the
`lib` and `include` directories into the `example/thirdparty` directory.
This example dir is used
to generate an example bazel project with `ray cpp
--generate-bazel-project-template-to /tmp/ray`. However, the script
already finds the "real"
`include`/`lib` directories and copies those in at execution time (just
deleting the ones we package in anwyway). You can see this happen
[here](https://github.com/ray-project/ray/blob/2d1ca70e9507480eac37b65796ae0da1dffc5084/python/ray/scripts/scripts.py#L2621).

## Related issue number

none, but can create if preferred

## Checks

- [x] I've signed off every commit(by using the -s flag, i.e., `git
commit -s`) in this PR.
- [x] I've run `scripts/format.sh` to lint the changes in this PR.
- [ N/A ] I've included any doc changes needed for
https://docs.ray.io/en/master/.
- [x] I've made sure the tests are passing. Note that there might be a
few flaky tests, see the recent failures at https://flakey-tests.ray.io/
- Testing Strategy

Run any build as per the docs

```
docker run -ti --rm     -e BUILDKITE_COMMIT="$(git rev-parse HEAD)"     -e BUILD_ONE_PYTHON_ONLY=py311     -w /ray -v "$(pwd)":/ray     quay.io/pypa/manylinux2014_x86_64:2024-07-02-9ac04ee     /ray/python/build-wheel-manylinux2014.sh
```

install the wheel, and see `<site>/ray/cpp` has `include` and `lib`, and
`example`, but no `example/thirdparty/{include,lib}`

then running `ray cpp --generate-bazel-project-template-to /tmp/ray` to
see `thirdparty/{include,lib}` was still available there.

```
$ docker run -it --rm -w /ray -v "$(pwd)":/ray  python:3.9.23-bookworm /bin/bash
...
root@fb2a260f25a6:/ray# pip install ./.whl/ray*
Processing ./.whl/ray-3.0.0.dev0-cp39-cp39-manylinux2014_x86_64.whl
Processing ./.whl/ray_cpp-3.0.0.dev0-cp39-cp39-manylinux2014_x86_64.whl
...
root@fb2a260f25a6:/ray# ray cpp --generate-bazel-project-template-to /tmp/ray
Project template generated to /tmp/ray
To build and run this template, run
    cd /tmp/ray && bash run.sh
root@fb2a260f25a6:/ray# ls -al /tmp/ray/thirdparty/
total 16
drwxr-xr-x 4 root root 4096 Jul 11 19:52 .
drwxr-xr-x 3 root root 4096 Jul 11 19:52 ..
drwxr-xr-x 6 root root 4096 Jul 11 19:52 include
drwxr-xr-x 2 root root 4096 Jul 11 19:52 lib
root@fb2a260f25a6:/ray# ls -al /tmp/ray/thirdparty/lib
total 36496
drwxr-xr-x 2 root root     4096 Jul 11 19:52 .
drwxr-xr-x 4 root root     4096 Jul 11 19:52 ..
-rwxr-xr-x 1 root root 37363304 Jul 11 19:52 libray_api.so
root@fb2a260f25a6:/ray# ls -al /tmp/ray/thirdparty/include/
total 32
drwxr-xr-x  6 root root 4096 Jul 11 19:52 .
drwxr-xr-x  4 root root 4096 Jul 11 19:52 ..
drwxr-xr-x 27 root root 4096 Jul 11 19:52 boost
drwxr-xr-x  8 root root 4096 Jul 11 19:52 msgpack
-rw-r--r--  1 root root  526 Jul 11 19:52 msgpack.h
-rw-r--r--  1 root root  648 Jul 11 19:52 msgpack.hpp
drwxr-xr-x  2 root root 4096 Jul 11 19:52 nlohmann
drwxr-xr-x  3 root root 4096 Jul 11 19:52 ray
```

Signed-off-by: Mark Molinaro <[email protected]>

Author: markjm

cpp/BUILD.bazel

@@ -164,11 +164,6 @@ genrule(
         cp -f -r $$WORK_DIR/external/boost/boost/*.hpp "$$BOOST_DIR" &&
         cp -f $(locations libray_api.so) "$$PY_CPP_DIR/lib/" &&
         cp -f -r "$$WORK_DIR/cpp/include/ray" "$$PY_CPP_DIR/include" &&
-        THIRDPARTY_DIR="$$WORK_DIR/cpp/example/thirdparty" &&
-        rm -rf $$THIRDPARTY_DIR &&
-        mkdir $$THIRDPARTY_DIR &&
-        cp -f -r "$$PY_CPP_DIR/include" $$THIRDPARTY_DIR &&
-        cp -f -r "$$PY_CPP_DIR/lib" $$THIRDPARTY_DIR &&
         cp -f -r "$$WORK_DIR/cpp/example" "$$PY_CPP_DIR" &&
         echo "$$WORK_DIR" > $@
     """,