Bump actions/checkout in the github-actions-dependencies group

Bumps the github-actions-dependencies group with 1 update: [actions/checkout](https://github.com/actions/checkout).


Updates `actions/checkout` from 5 to 6
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: github-actions-dependencies
...

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

Author: dependabot[bot]

.github/workflows/elixir.yml

@@ -36,7 +36,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 

.github/workflows/update-asdf.yaml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Update asdf
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       # Set the user based on https://github.com/actions/checkout/issues/13#issuecomment-724415212
       - run: |
           git config --global user.email "41898282+github-actions[bot]@users.noreply.github.com"