Fix ambiguity errors in `a_star` and `steiner_tree` #114

	name: CI
	on:
	push:
	branches:
	- main
	tags: '*'
	pull_request:
	concurrency:
	# Skip intermediate builds: always.
	# Cancel intermediate builds: only if it is a pull request build.
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}
	jobs:
	test:
	name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	version:
	- '1.7'
	- '1'
	os:
	- ubuntu-latest
	- macOS-latest
	- windows-latest
	arch:
	- x64
	steps:
	- uses: actions/checkout@v2
	- uses: julia-actions/setup-julia@v1
	with:
	version: ${{ matrix.version }}
	arch: ${{ matrix.arch }}
	- uses: julia-actions/cache@v1
	- uses: julia-actions/julia-buildpkg@v1
	- uses: julia-actions/julia-runtest@v1
	- uses: julia-actions/julia-processcoverage@v1
	- uses: codecov/codecov-action@v2
	with:
	files: lcov.info
	docs:
	name: Documentation
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: julia-actions/setup-julia@v1
	with:
	version: '1'
	- uses: julia-actions/julia-buildpkg@v1
	- uses: julia-actions/julia-docdeploy@v1
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	DOCUMENTER_KEY: ${{ secrets.DOCUMENTER_KEY }}
	- run: \|
	julia --project=docs -e '
	using Documenter: DocMeta, doctest
	using DataGraphs
	DocMeta.setdocmeta!(DataGraphs, :DocTestSetup, :(using DataGraphs); recursive=true)
	doctest(DataGraphs)'

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