Update to actions/checkout@v5

Author: treeform

.github/workflows/build.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v5
     - uses: jiro4989/setup-nim-action@v2
       with:
         repo-token: ${{ secrets.GITHUB_TOKEN }}