[CI] Cancel workflows for stale commits automatically (#144)

Author: kmichaelk

.github/workflows/main.yml

@@ -7,6 +7,10 @@ on:
     - cron: '0 12 * * *'
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   ubuntu-gcc-build:
     runs-on: ubuntu-latest

.github/workflows/static-analysis-pr.yml

@@ -2,6 +2,10 @@ name: Static analysis
 
 on: [pull_request]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   clang-tidy:
     runs-on: ubuntu-latest

.github/workflows/static-analysis.yml

@@ -2,6 +2,10 @@ name: Static analysis
 
 on: [push, pull_request]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   clang-format:
     runs-on: ubuntu-latest