Fixed span clone concurrency issues #251

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	# This workflow will build a Java project with Maven
	# For more information see: https://help.github.com/actions/language-and-framework-guides/building-and-testing-java-with-maven

	name: build

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

	jobs:
	build:

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v2
	with:
	fetch-depth: 2
	- name: Set up JDK 1.8
	uses: actions/setup-java@v1
	with:
	java-version: 1.8
	- name: Build with Maven
	run: mvn clean install -DskipTests -B -V
	&& sh ./check_format.sh
	&& mvn clean test
	- name: Codecov
	uses: codecov/codecov-action@v1

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