Bump flink from 2.1.0-java21 to 2.1.1-java21

Bumps flink from 2.1.0-java21 to 2.1.1-java21.

---
updated-dependencies:
- dependency-name: flink
  dependency-version: 2.1.1-java21
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

Dockerfile

@@ -2,7 +2,7 @@ FROM gradle:9.2.0-jdk21 as builder
 COPY . .
 RUN gradle shadowJar
 
-FROM flink:2.1.0-java21
+FROM flink:2.1.1-java21
 RUN echo "metrics.reporters: prom" >> "$FLINK_HOME/conf/config.yaml"; \
     echo "metrics.reporter.prom.factory.class: org.apache.flink.metrics.prometheus.PrometheusReporterFactory" >> "$FLINK_HOME/conf/config.yaml"
 COPY --from=builder /home/gradle/build/libs/*.jar $FLINK_HOME/usrlib/