Normalize iwyu return code when filtering implementation header sugge… #125

	name: test ubuntu 20.04
	on: [push]
	jobs:
	build:
	runs-on: [ubuntu-latest]
	steps:
	- name: Checkout repository
	uses: actions/checkout@v4
	- name: Install 7 hooks, python, pip
	run: sudo apt install clang clang-format clang-tidy uncrustify cppcheck iwyu python3 python3-pip
	- name: Install latest oclint (21.05)
	run: \|
	wget https://github.com/oclint/oclint/releases/download/v21.05/oclint-21.05-llvm-12.0.0-x86_64-linux-ubuntu-20.04.tar.gz
	tar -xvzf oclint-21.05-llvm-12.0.0-x86_64-linux-ubuntu-20.04.tar.gz
	sudo cp -v oclint-21.05/bin/oclint /usr/local/bin/
	sudo cp -vr oclint-21.05/lib/* /usr/local/lib/
	oclint --version
	- name: Install pip dependencies
	run: pip install cpplint pytest black pre-commit
	- name: Install hooks locally
	run: pip install .
	- name: Get command versions
	run: \|
	clang-format --version
	clang-tidy --version
	cppcheck --version
	cpplint --version
	iwyu --version
	oclint --version
	- name: Get python library versions
	run: \|
	pytest --version
	pre-commit --version
	- name: Run tests
	run: python3 -m pytest -x -vvv

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