Bump alpine from 3.18.3 to 3.18.4 in /docker

Bumps alpine from 3.18.3 to 3.18.4.

---
updated-dependencies:
- dependency-name: alpine
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

docker/Dockerfile

@@ -14,7 +14,7 @@
 #  limitations under the License.
 #
 
-FROM alpine:3.18.3@sha256:7144f7bab3d4c2648d7e59409f15ec52a18006a128c733fcff20d3a4a54ba44a as staging_area
+FROM alpine:3.18.4@sha256:eece025e432126ce23f223450a0326fbebde39cdf496a85d8c016293fc851978 as staging_area
 
 RUN apk --no-cache add openjdk17-jdk openjdk17-jmods
 
@@ -68,7 +68,7 @@ RUN jlink \
     --strip-java-debug-attributes \
     --output "$JAVA_MINIMAL"
 
-FROM alpine:3.18.3@sha256:7144f7bab3d4c2648d7e59409f15ec52a18006a128c733fcff20d3a4a54ba44a
+FROM alpine:3.18.4@sha256:eece025e432126ce23f223450a0326fbebde39cdf496a85d8c016293fc851978
 
 ENV JAVA_HOME=/opt/java-minimal
 ENV PATH="$PATH:$JAVA_HOME/bin"