fix runs-on, yamllint

.github/workflows/ci.yml

@@ -2,18 +2,21 @@ name: Build and test
 
 on:
   push:
-    branches: [ master ]
+    branches:
+      - master
   pull_request:
-    branches: [ master ]
+    branches:
+      - master
   schedule:
     - cron: '0 4 * * 0'
 
 jobs:
 
   Windows-test:
-    runs-on: [windows-2019, windows-2022]
+    runs-on: ${{ matrix.os }}
     strategy:
       matrix:
+        os: [windows-2019, windows-2022]
         config: [Debug, Release]
     steps:
       - uses: actions/checkout@v4
@@ -51,7 +54,10 @@ jobs:
           cmake --build . --target test
 
   Unix-test-coverage:
-    runs-on: [ubuntu-22.04, macos-14]
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-22.04, macos-14]
     steps:
       - uses: actions/checkout@v4