🌱 Update image docker.io/library/alpine to v3.21.4

| datasource | package                  | from   | to     |
| ---------- | ------------------------ | ------ | ------ |
| docker     | docker.io/library/alpine | 3.21.3 | 3.21.4 |

Author: syself-bot[bot]

images/cache/Dockerfile

@@ -13,7 +13,7 @@
 # limitations under the License.
 
 
-FROM docker.io/library/alpine:3.21.3@sha256:a8560b36e8b8210634f77d9f7f9efd7ffa463e380b75e2e74aff4511df3ef88c AS import-cache
+FROM docker.io/library/alpine:3.21.4@sha256:b6a6be0ff92ab6db8acd94f5d1b7a6c2f0f5d10ce3c24af348d333ac6da80685 AS import-cache
 
 RUN --mount=type=bind,target=/host-tmp \
     --mount=type=cache,target=/root/.cache \
@@ -27,7 +27,7 @@ RUN --mount=type=bind,target=/host-tmp \
       tar xzf /host-tmp/go-pkg-cache.tar.gz --no-same-owner -C /go/pkg; \
     fi
 
-FROM docker.io/library/alpine:3.21.3@sha256:a8560b36e8b8210634f77d9f7f9efd7ffa463e380b75e2e74aff4511df3ef88c AS cache-creator
+FROM docker.io/library/alpine:3.21.4@sha256:b6a6be0ff92ab6db8acd94f5d1b7a6c2f0f5d10ce3c24af348d333ac6da80685 AS cache-creator
 RUN --mount=type=cache,target=/root/.cache \
     --mount=type=cache,target=/go/pkg \
     tar czf /tmp/go-build-cache.tar.gz -C /root/.cache/go-build . ; \