fix worker freeze from two sequential `wait()` when a task is emplace… #129

	name: 🐧 Ubuntu

	on: [push, pull_request]

	concurrency:
	group: ${{ github.ref }}-${{ github.head_ref }}-ubuntu
	cancel-in-progress: true

	jobs:
	build_gcc:
	name: GCC
	runs-on: ubuntu-22.04
	if: github.event.pull_request.draft == false
	env:
	CXXFLAGS: "-Wall -Wextra -Wshadow"
	steps:
	- uses: actions/checkout@v2
	- name: install dependencies
	run: \|
	.github/workflows/dependencies/gcc.sh
	- name: CCache Cache
	uses: actions/cache@v2
	# - once stored under a key, they become immutable (even if local cache path content changes)
	# - for a refresh the key has to change, e.g., hash of a tracked file in the key
	with:
	path: \|
	~/.ccache
	~/.cache/ccache
	key: ccache-openmp-cxxminimal-${{ hashFiles('.github/workflows/ubuntu.yml') }}-${{ hashFiles('CMakeLists.txt') }}
	restore-keys: \|
	ccache-openmp-cxxminimal-${{ hashFiles('.github/workflows/ubuntu.yml') }}-
	ccache-openmp-cxxminimal-
	- name: build RedGrapes
	run: \|
	cmake \
	-S . \
	-B build \
	-G Ninja \
	-DCMAKE_BUILD_TYPE=Debug \
	-DCMAKE_CXX_COMPILER_LAUNCHER=ccache \
	-DCMAKE_VERBOSE_MAKEFILE=ON \
	-DBUILD_TESTING=ON \
	-DredGrapes_BUILD_EXAMPLES=ON

	cmake --build build -j 2

	- name: test RedGrapes
	run: \|
	ctest --test-dir build/test --output-on-failure

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