Switch to sync.RWMutex #19

	name: Go
	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]
	jobs:

	build:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	with:
	fetch-depth: 0

	- name: Set up Go
	uses: actions/setup-go@v3
	with:
	go-version: ^1.20
	cache: true

	- name: test
	run: go test -race -coverprofile=profile.cov -v

	- name: Send coverage
	uses: shogo82148/actions-goveralls@v1
	with:
	path-to-profile: profile.cov
	parallel: true

	# notifies that all test jobs are finished.
	finish:
	needs: build
	runs-on: ubuntu-latest
	steps:
	- uses: shogo82148/actions-goveralls@v1
	with:
	parallel-finished: true

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