chore(deps): update docker docker tag to v29 (#924)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker | stage | major | `28-dind-rootless` → `29-dind-rootless` |
| docker | stage | major | `28-dind` → `29-dind` |

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Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-on: https://gitea.com/gitea/runner/pulls/924
Reviewed-by: silverwind <2021+silverwind@noreply.gitea.com>
Co-authored-by: Renovate Bot <renovate-bot@gitea.com>
Co-committed-by: Renovate Bot <renovate-bot@gitea.com>

Dockerfile

@@ -17,7 +17,7 @@ RUN make clean && make build
 ### DIND VARIANT
 #
 #
-FROM docker:28-dind AS dind
+FROM docker:29-dind AS dind
 
 RUN apk add --no-cache s6 bash git tzdata
 
@@ -32,7 +32,7 @@ ENTRYPOINT ["s6-svscan","/etc/s6"]
 ### DIND-ROOTLESS VARIANT
 #
 #
-FROM docker:28-dind-rootless AS dind-rootless
+FROM docker:29-dind-rootless AS dind-rootless
 
 USER root
 RUN apk add --no-cache s6 bash git tzdata