Fix use with CMake 3.21 and older #109

	name: toml-test

	on: [push, pull_request]

	jobs:
	toml-test:
	runs-on: Ubuntu-22.04
	strategy:
	matrix:
	compiler: ['g++-12']
	standard: ['11', '14', '17', '20']
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	with:
	submodules: true
	- name: Install
	run: \|
	sudo apt update
	sudo apt install -y ${{ matrix.compiler }}
	- name: Setup Go
	uses: actions/setup-go@v5
	- name: Configure
	run: \|
	cmake -B build/ -DBUILD_TESTING=OFF -DCMAKE_CXX_COMPILER=${{ matrix.compiler }} -DCMAKE_CXX_STANDARD=${{ matrix.standard }} -DTOML11_BUILD_TOML_TESTS=ON
	- name: Build
	run: \|
	cmake --build build/
	- name: Test
	run: \|
	go install github.com/toml-lang/toml-test/cmd/toml-test@latest
	toml-test ./build/tests/toml11_decoder
	# skipped tests does not conform the latest commit in toml-lang/toml
	toml-test -toml 1.1.0 ./build/tests/toml11_decoder_v1_1_0 -skip invalid/control/comment-del,invalid/control/comment-lf,invalid/control/comment-us
	toml-test -encoder ./build/tests/toml11_encoder

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