Cancel previous workflow runs

Author: brandonwillard

.github/workflows/pypi.yml

@@ -9,6 +9,13 @@ on:
   release:
     types: [published]
 
+# Cancels all previous workflow runs for pull requests that have not completed.
+concurrency:
+  # The concurrency group contains the workflow name and the branch name for pull requests
+  # or the commit hash for any other events.
+  group: ${{ github.workflow }}-${{ github.event_name == 'pull_request' && github.head_ref || github.sha }}
+  cancel-in-progress: true
+
 jobs:
   build:
     name: Build source distribution

.github/workflows/tests.yml

@@ -8,6 +8,13 @@ on:
     branches:
       - master
 
+# Cancels all previous workflow runs for pull requests that have not completed.
+concurrency:
+  # The concurrency group contains the workflow name and the branch name for pull requests
+  # or the commit hash for any other events.
+  group: ${{ github.workflow }}-${{ github.event_name == 'pull_request' && github.head_ref || github.sha }}
+  cancel-in-progress: true
+
 jobs:
   changes:
     name: "Check for changes"