Limit concurrency on GitHub Actions

https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#concurrency

.github/workflows/bench.yml

@@ -4,6 +4,10 @@ on:
       - main
   pull_request:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.sha }}
+  cancel-in-progress: true
+
 name: Benchmark
 
 jobs:

.github/workflows/ci.yml

@@ -6,6 +6,10 @@ on:
       - main
   pull_request:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.sha }}
+  cancel-in-progress: true
+
 env:
   CARGO_TERM_COLOR: always
 

.github/workflows/guide.yml

@@ -8,6 +8,10 @@ on:
   release:
     types: [published]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.sha }}
+  cancel-in-progress: true
+
 env:
   CARGO_TERM_COLOR: always