Bump actions/checkout from 5.0.0 to 6.0.0

Bumps [actions/checkout](https://github.com/actions/checkout) from 5.0.0 to 6.0.0.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v5.0.0...v6.0.0)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: 6.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/build_sprites.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkou️t
-        uses: actions/checkout@v5.0.0
+        uses: actions/checkout@v6.0.0
 
       - name: Setup node
         uses: actions/setup-node@v5.0.0

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
         node-version: [20]
 
     steps:
-    - uses: actions/checkout@v5.0.0
+    - uses: actions/checkout@v6.0.0
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v5.0.0
       with: