Update Doxyfile to use HTML5 DOCTYPE and modern settings #4

	name: C++ CI

	on:
	push:
	branches: [ main ]
	pull_request:
	branches: [ main ]

	permissions:
	contents: write

	jobs:
	build:
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v2

	- name: Install dependencies
	run: \|
	sudo apt-get update
	sudo apt-get install -y cmake g++ libgtest-dev doxygen graphviz
	cd /usr/src/gtest
	sudo cmake CMakeLists.txt
	sudo make
	sudo cp lib/*.a /usr/lib

	- name: Configure CMake
	run: cmake -B build -DBUILD_TESTING=ON

	- name: Build
	run: cmake --build build

	- name: Run tests
	run: \|
	cd build
	ctest --output-on-failure

	- name: Generate documentation
	run: doxygen Doxyfile

	- name: Deploy documentation
	uses: peaceiris/actions-gh-pages@v3
	if: github.ref == 'refs/heads/main'
	with:
	github_token: ${{ secrets.GITHUB_TOKEN }}
	publish_dir: ./docs/html

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