chore(deps): update actions/checkout action to v5 (#39)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://redirect.github.com/actions/checkout) |
action | major | `v4` -> `v5` |

---

### Release Notes

<details>
<summary>actions/checkout (actions/checkout)</summary>

### [`v5`](https://redirect.github.com/actions/checkout/compare/v4...v5)

[Compare
Source](https://redirect.github.com/actions/checkout/compare/v4...v5)

</details>

---

### Configuration

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Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

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rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

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View the [repository job
log](https://developer.mend.io/github/morten-olsen/homelab-operator).

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Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

.github/workflows/main.yml

@@ -27,7 +27,7 @@ jobs:
     name: Build
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
       - uses: actions/setup-node@v5
         with:
@@ -81,7 +81,7 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
       - name: Upload Release Asset
         id: upload-release-asset

.github/workflows/publish-backup-tag.yml

@@ -31,7 +31,7 @@ jobs:
     name: Release
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
         with:
           fetch-depth: 0
 

.github/workflows/publish-tag.yml

@@ -31,7 +31,7 @@ jobs:
     name: Release
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
         with:
           fetch-depth: 0
 

.github/workflows/renovate.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       - name: Self-hosted Renovate
         uses: renovatebot/github-action@v40.3.6
         with: