ci: bump actions/checkout from 6.0.2 to 6.0.3 in the actions group

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


Updates `actions/checkout` from 6.0.2 to 6.0.3
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](de0fac2e45...df4cb1c069)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: 6.0.3
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: actions
...

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

.github/workflows/ci.yml

@@ -26,7 +26,7 @@ jobs:
       - name: Configure git
         run: git config --global --add safe.directory '*'
       - name: Checkout
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           persist-credentials: false
       - name: Install markdownlint
@@ -71,7 +71,7 @@ jobs:
       options: --privileged --cgroupns=host -v /var/lib/containers -v /var/tmp -v /tmp
     steps:
       - name: Checkout
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           persist-credentials: false
       - name: Install tools

.github/workflows/msrv-bump.yml

@@ -21,7 +21,7 @@ jobs:
       - name: Configure git
         run: git config --global --add safe.directory '*'
       - name: Checkout
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           persist-credentials: false
 

.github/workflows/zizmor.yml

@@ -16,7 +16,7 @@ jobs:
       security-events: write # Required to upload SARIF files
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           persist-credentials: false