Bump the ci-dependencies group across 1 directory with 2 updates

Bumps the ci-dependencies group with 2 updates in the / directory: [actions/checkout](https://github.com/actions/checkout) and [withastro/action](https://github.com/withastro/action).


Updates `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@08c6903...1af3b93)

Updates `withastro/action` from 4.1.0 to 5.0.1
- [Release notes](https://github.com/withastro/action/releases)
- [Commits](withastro/action@77fad83...9811f92)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: 6.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: ci-dependencies
- dependency-name: withastro/action
  dependency-version: 5.0.1
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: ci-dependencies
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/site-deploy.yaml

@@ -14,12 +14,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: "Checkout repository"
-        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           fetch-depth: 0
 
       - name: "Install, build, and upload your site"
-        uses: withastro/action@77fad83745446cf039d76af7037b782f1af80749 # v4.1.0
+        uses: withastro/action@9811f9299d5d37ca0416ca85cee333c7c9485cd1 # v5.0.1
 
   deploy:
     if: ${{ github.ref == 'refs/heads/main' }}