Bump actions/checkout from 5 to 6 (#278)

Author: jason-fox

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Git checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Calculate short SHA
         uses: benjlevesque/short-sha@v3.0

.github/workflows/prettier.yml

@@ -17,7 +17,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           # Make sure the actual branch is checked out when running on pull requests
           ref: ${{ github.ref }}