build(deps): bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/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
...

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

Author: dependabot[bot]

.github/workflows/next.yml

@@ -16,7 +16,7 @@ jobs:
     name: debian staging build container
     steps:
       - name: Check out repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v3
       - name: Set up Docker Buildx
@@ -44,7 +44,7 @@ jobs:
     container:
       image: ghcr.io/linux-nvme/debian.staging:next
     steps:
-     - uses: actions/checkout@v5
+     - uses: actions/checkout@v6
      - name: build
        run: |
          scripts/build-muon.sh
@@ -65,7 +65,7 @@ jobs:
     name: debian build containers
     steps:
       - name: Check out repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Download artifacts
         uses: actions/download-artifact@v6
         with:
@@ -103,7 +103,7 @@ jobs:
     name: ubuntu cross container
     steps:
       - name: Check out repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v3
       - name: Set up Docker Buildx

.github/workflows/release.yml

@@ -16,7 +16,7 @@ jobs:
     name: debian staging build container
     steps:
       - name: Check out repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v3
       - name: Set up Docker Buildx
@@ -44,7 +44,7 @@ jobs:
     container:
       image: ghcr.io/linux-nvme/debian.staging:main
     steps:
-     - uses: actions/checkout@v5
+     - uses: actions/checkout@v6
      - name: build
        run: |
          scripts/build-muon.sh
@@ -65,7 +65,7 @@ jobs:
     name: debian build containers
     steps:
       - name: Check out repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Get release
         run: echo "RELEASE_VERSION=${GITHUB_REF#refs/tags/}" >> $GITHUB_ENV
       - name: Download artifacts
@@ -106,7 +106,7 @@ jobs:
     name: ubuntu cross container
     steps:
       - name: Check out repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Get release
         run: echo "RELEASE_VERSION=${GITHUB_REF#refs/tags/}" >> $GITHUB_ENV
       - name: Set up QEMU