[doc] Add R code tabs to custom_metric_obj tutorial #3947

	name: XGBoost CI (Lint)

	on:
	push:
	branches:
	- master
	- 'release_*'
	pull_request:

	permissions:
	contents: read # to fetch code (actions/checkout)

	concurrency:
	group: ${{ github.workflow }}-${{ github.event.pull_request.number \|\| github.ref }}
	cancel-in-progress: true

	env:
	BRANCH_NAME: >-
	${{ github.event.pull_request.number && 'PR-' }}${{ github.event.pull_request.number \|\| github.ref_name }}

	jobs:
	ci-configure:
	name: Configure variables for CI
	uses: ./.github/workflows/ci_configure.yml
	with:
	tag-prefix: lint

	clang-tidy:
	name: Run clang-tidy
	needs: ci-configure
	runs-on:
	- runs-on=${{ github.run_id }}
	- runner=linux-amd64-cpu
	- tag=lint-clang-tidy-clang-cuda
	container:
	image: ${{ needs.ci-configure.outputs.docker_registry }}/xgb-ci.gpu_build_rockylinux8:${{ needs.ci-configure.outputs.image_tag }}
	credentials:
	username: ${{ needs.ci-configure.outputs.docker_username }}
	password: ${{ needs.ci-configure.outputs.docker_password }}
	steps:
	- uses: actions/checkout@v6.0.2
	with:
	submodules: "true"
	- name: Run clang-tidy on clang-CUDA compile database
	run: bash ops/pipeline/run-clang-tidy-clang-cuda.sh

	python-mypy:
	runs-on: ubuntu-latest
	name: Type checks for the Python package
	steps:
	- uses: actions/checkout@v6.0.2
	with:
	submodules: 'true'
	- uses: dmlc/xgboost-devops/actions/miniforge-setup@main
	with:
	environment-name: python_lint
	environment-file: ops/conda_env/python_lint.yml
	- name: Run mypy
	shell: bash -el {0}
	run: \|
	python ops/script/type_check_python.py

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