Schedule monthly run for test CI workflow (#9)

* Make all CI workflows cancelable

* Schedule the test CI workflow monthly

Author: mdpiper

.github/workflows/format.yml

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

.github/workflows/lint.yml

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

.github/workflows/test.yml

@@ -1,6 +1,14 @@
 name: Test
 
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: '24 4 3 * *'  # 4:24a on third day of the month
+
+concurrency:
+  group: ${{ github.ref }}-${{ github.workflow }}
+  cancel-in-progress: true
 
 jobs:
   build-test-unix: