ci: Add concurrency cancellation

Every time I (or someone else) force pushes to re-add the DCO
we're wasting resources and/or just have added latency.

Signed-off-by: Colin Walters <[email protected]>

Author: cgwalters

.github/workflows/ci.yml

@@ -13,6 +13,10 @@ on:
 env:
   CARGO_TERM_COLOR: always
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   tests:
     runs-on: ubuntu-latest

.github/workflows/integration.yml

@@ -15,6 +15,10 @@ on:
   pull_request_target:
     types: [opened, synchronize, reopened]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 env:
   AWS_REGION: us-east-1