docs: add new snippet to README for `wait_for_tasks()` #241

	name: Install

	on:
	push:
	branches:
	- master
	pull_request:
	branches:
	- master

	env:
	CTEST_OUTPUT_ON_FAILURE: 1
	CPM_SOURCE_CACHE: ${{ github.workspace }}/cpm_modules

	jobs:
	build:
	runs-on: ubuntu-20.04

	env:
	CPP_STANDARD: 20

	steps:
	- uses: actions/checkout@v3

	- uses: actions/cache@v3
	with:
	path: "**/cpm_modules"
	key: ${{ github.workflow }}-cpm-modules-${{ hashFiles('/CMakeLists.txt', '/*.cmake') }}

	- name: set up GCC
	uses: egor-tensin/setup-gcc@v1
	with:
	version: 11
	platform: x64

	- name: build and install library
	run: \|
	cmake -S. -Bbuild -DCMAKE_BUILD_TYPE=Release -DTP_BUILD_EXAMPLES=OFF -DTP_BUILD_TESTS=ON -DTP_BUILD_BENCHMARKS=OFF -DCMAKE_INSTALL_PREFIX="/usr/local"
	sudo cmake --build build --target install
	rm -rf build

	- name: configure
	run: cmake -Stest -Bbuild -DTEST_INSTALLED_VERSION=1 -Dthread-pool_DIR="/usr/local/lib/cmake/thread-pool-0.6.0/"

	- name: build
	run: cmake --build build --config Debug -j4

	- name: test
	run: \|
	cd build
	ctest --build-config Debug

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