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](https://github.com/actions/checkout/compare/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] <support@github.com>

.github/workflows/onpush_builder.yaml

@@ -23,7 +23,7 @@ jobs:
       changedAddons: ${{ steps.find_addons.outputs.changed_addons }}
     steps:
       - name: Checkout repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Find changed addon directories
         id: find_addons
         run: |
@@ -44,7 +44,7 @@ jobs:
       matrix:
         addon: ${{ fromJSON(needs.detect-changed-addons.outputs.changedAddons) }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       # ────────────────────────────────────────────────────────────────
       # 1. Replace non-printable Unicode spaces  ␣  and
       #    convert Windows line endings (CRLF) → Unix (LF)
@@ -99,7 +99,7 @@ jobs:
       matrix:
         addon: ${{ fromJSON(needs.detect-changed-addons.outputs.changedAddons) }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Run Home Assistant Add-on Lint
         uses: frenck/action-addon-linter@v2
         with:
@@ -117,7 +117,7 @@ jobs:
         addon: ${{ fromJSON(needs.detect-changed-addons.outputs.changedAddons) }}
         arch: ["aarch64", "amd64", "armv7"]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Resolve Symlinks (in repo)
         run: |
           find . -type l | while read -r link; do
@@ -194,7 +194,7 @@ jobs:
       matrix:
         addon: ${{ fromJSON(needs.detect-changed-addons.outputs.changedAddons) }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 1
       - name: Update changelog for minor versions
@@ -239,7 +239,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repo
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0