Merge branch 'master' into merge-master-into-develop

# Conflicts:
#	.github/workflows/main.yml
#	.github/workflows/release.yml
#	.pre-commit-config.yaml
#	CHANGELOG.md
#	CONTRIBUTING.md
#	docs/docs/cli.md
#	get-poetry.py
#	make-linux-release.sh
#	poetry.lock
#	poetry/__version__.py
#	poetry/console/commands/export.py
#	poetry/console/commands/self/update.py
#	poetry/installation/pip_installer.py
#	poetry/masonry/api.py
#	poetry/masonry/builders/builder.py
#	poetry/masonry/builders/sdist.py
#	poetry/masonry/utils/package_include.py
#	poetry/masonry/utils/tags.py
#	poetry/packages/__init__.py
#	poetry/packages/directory_dependency.py
#	poetry/packages/file_dependency.py
#	poetry/packages/package.py
#	poetry/packages/url_dependency.py
#	poetry/packages/utils/utils.py
#	poetry/packages/vcs_dependency.py
#	poetry/puzzle/provider.py
#	poetry/repositories/installed_repository.py
#	poetry/repositories/legacy_repository.py
#	poetry/repositories/pypi_repository.py
#	poetry/semver/__init__.py
#	poetry/semver/patterns.py
#	poetry/utils/env.py
#	poetry/utils/helpers.py
#	poetry/utils/inspector.py
#	poetry/vcs/__init__.py
#	poetry/vcs/git.py
#	pyproject.toml
#	tests/conftest.py
#	tests/installation/fixtures/with-directory-dependency-poetry-transitive.test
#	tests/json/test_poetry_schema.py
#	tests/masonry/builders/test_sdist.py
#	tests/masonry/builders/test_wheel.py
#	tests/masonry/test_api.py
#	tests/masonry/utils/test_package_include.py
#	tests/packages/test_main.py
#	tests/packages/test_package.py
#	tests/puzzle/test_solver.py
#	tests/repositories/fixtures/installed/vendor/py3.7/attrs-19.3.0.dist-info/METADATA
#	tests/repositories/test_installed_repository.py
#	tests/repositories/test_legacy_repository.py
#	tests/vcs/test_git.py