ci(github-action): update action https://data.forgejo.org/actions/checkout (v6.0.2 ➔ v6.0.3) (#799)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [https://data.forgejo.org/actions/checkout](https://data.forgejo.org/actions/checkout) | action | patch | `v6.0.2` → `v6.0.3` |

---

### Release Notes

<details>
<summary>actions/checkout (https://data.forgejo.org/actions/checkout)</summary>

### [`v6.0.3`](https://data.forgejo.org/actions/checkout/blob/HEAD/CHANGELOG.md#v603)

[Compare Source](https://data.forgejo.org/actions/checkout/compare/v6.0.2...v6.0.3)

- Fix checkout init for SHA-256 repositories by [@&#8203;yaananth](https://github.com/yaananth) in [#&#8203;2439](actions/checkout#2439)
- fix: expand merge commit SHA regex and add SHA-256 test cases by [@&#8203;yaananth](https://github.com/yaananth) in [#&#8203;2414](actions/checkout#2414)

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

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

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the 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

---

This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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Reviewed-on: https://git.erwanleboucher.dev/eleboucher/homelab/pulls/799

Author: bot-owl

.forgejo/workflows/flux-oci-push.yaml

@@ -24,7 +24,7 @@ jobs:
     outputs:
       digest-url: ${{ steps.push.outputs.digest-url }}
     steps:
-      - uses: https://data.forgejo.org/actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: https://data.forgejo.org/actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
 
       - name: Install Flux CLI
         run: |