Update docker/build-push-action action to v7

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| grafana/tempo |  | digest | `512af54` -> `cfe9b6a` |
| [oven/bun](https://github.com/oven-sh/bun) | stage | patch | `1.3.3` -> `1.3.4` |
| [oven/bun](https://github.com/oven-sh/bun) |  | patch | `1.3.3` -> `1.3.4` |

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Reviewed-on: #74
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Co-committed-by: Renovate Bot <renovate-bot@valverde.cloud>

.gitea/workflows/build.yaml

@@ -39,7 +39,7 @@ jobs:
             latest=true
 
       - name: Build
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           context: .
           file: ./Dockerfile