cancel the outdated action (#91)

.github/workflows/build.yml

@@ -11,6 +11,10 @@ on:
       - 'README.md'
       - 'docs/**'
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   test:
     runs-on: ubuntu-18.04

.github/workflows/lint.yml

@@ -2,6 +2,10 @@ name: lint
 
 on: [push, pull_request]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   lint:
     runs-on: ubuntu-latest

.github/workflows/publish-to-pypi.yml

@@ -2,6 +2,10 @@ name: deploy
 
 on: push
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   deploy:
     runs-on: ubuntu-18.04