Update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/build.yml

@@ -4,7 +4,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: actions/setup-node@v4
         with:
           node-version: 18
@@ -15,7 +15,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: actions/setup-node@v4
         with:
           node-version: 18