support indexmap 2.0.0 #50

	#
	# Configuration for GitHub-based CI, based on the stock GitHub Rust config.
	#
	name: Build

	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]

	jobs:
	check-style:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v2
	- name: Report cargo version
	run: cargo --version
	- name: Report rustfmt version
	run: cargo fmt -- --version
	- name: Check style
	run: cargo fmt -- --check

	build-and-test:
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ ubuntu-22.04, windows-2022, macos-12 ]
	steps:
	- uses: actions/checkout@v2
	- name: Build
	run: cargo build --tests --verbose
	- name: Run tests
	run: cargo test --verbose

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