chore(deps): update amazoncorretto docker tag to v21

Author: renovate[bot]

Dockerfile

@@ -5,7 +5,7 @@ COPY ./ /build
 
 RUN gradle shadowjar
 
-FROM amazoncorretto:17.0.16-alpine3.21
+FROM amazoncorretto:21.0.8-alpine3.21
 
 WORKDIR /home/GravenSupport
 COPY --from=builder /build/build/libs/*.jar /GravenSupport.jar