chore(deps): update ghcr.io/renovatebot/renovate:latest docker digest to 28672db (#24)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| ghcr.io/renovatebot/renovate | container | digest | `6ecdd98` -> `28672db` |

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### Configuration

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

🚦 **Automerge**: Enabled.

♻ **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.

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

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This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0MC4zNy4wIiwidXBkYXRlZEluVmVyIjoiNDAuMzcuMCIsInRhcmdldEJyYW5jaCI6Im1haW4iLCJsYWJlbHMiOltdfQ==-->

Reviewed-on: #24
Co-authored-by: Renovate Bot <renovatebot@schulze.network>
Co-committed-by: Renovate Bot <renovatebot@schulze.network>

.gitea/workflows/renovate.yaml

@@ -10,7 +10,7 @@ on:
 jobs:
   renovate:
     runs-on: ubuntu-latest
-    container: ghcr.io/renovatebot/renovate:latest@sha256:6ecdd98d4a227d350d72b04351fc2324d7f699c17b9bb98bafbfa4a8fd8afb5b
+    container: ghcr.io/renovatebot/renovate:latest@sha256:28672db33b95306a8c2787156102f48a86aece3a53441ef17fb32b7cf2841364
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
       - run: renovate