chore(deps): update docker/login-action action to v4 (#175)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [docker/login-action](https://github.com/docker/login-action) | action | major | `v3` → `v4` |

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### Release Notes

<details>
<summary>docker/login-action (docker/login-action)</summary>

### [`v4`](https://github.com/docker/login-action/compare/v3...v4)

[Compare Source](https://github.com/docker/login-action/compare/v3...v4)

</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 is behind base branch, 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).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0My41MS4xIiwidXBkYXRlZEluVmVyIjoiNDMuNTEuMSIsInRhcmdldEJyYW5jaCI6Im1haW4iLCJsYWJlbHMiOltdfQ==-->

Reviewed-on: #175
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

.gitea/workflows/release-image-gitea.yml

@@ -42,7 +42,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Login to Registry
-        uses: docker/login-action@v3
+        uses: docker/login-action@v4
         with:
           registry: ${{ vars.REPOSITORY_HOST }}
           username: ${{ gitea.actor }}

.gitea/workflows/release-image-harbor.yml

@@ -42,7 +42,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Login to Registry
-        uses: docker/login-action@v3
+        uses: docker/login-action@v4
         with:
           registry: ${{ vars.REGISTRY_HOST }}
           username: ${{ vars.REGISTRY_USER }}