Update eclipse-temurin Docker tag to v21.0.8_9-jre (#233)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| eclipse-temurin | final | patch | `21.0.7_6-jre` -> `21.0.8_9-jre` |

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Dockerfile

@@ -6,7 +6,7 @@ RUN gradle build
 
 
 
-FROM --platform=$TARGETPLATFORM eclipse-temurin:21.0.7_6-jre
+FROM --platform=$TARGETPLATFORM eclipse-temurin:21.0.8_9-jre
 
 WORKDIR /app
 COPY --from=builder /data/build/libs/Neptunes-Dashboard-4.1.0-all.jar /app/Neptunes-Dashboard.jar