ci: bump actions/checkout from 4.3.1 to 6.0.3

Bumps [actions/checkout](https://github.com/actions/checkout) from 4.3.1 to 6.0.3.
- [Release notes](https://github.com/actions/checkout/releases)
- [Commits](actions/checkout@v4.3.1...v6.0.3)

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

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -28,7 +28,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@v6.0.3
         with:
           fetch-depth: 0
           fetch-tags: true
@@ -104,7 +104,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
         with:
           fetch-depth: 0
           fetch-tags: true

.github/workflows/pack-and-publish.yml

@@ -24,7 +24,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@v6.0.3
         with:
           ref: ${{ inputs.branch }}
           fetch-depth: 0