Update .gitpod.Dockerfile

Author: cjbi

gitpod/.gitpod.Dockerfile

@@ -3,8 +3,8 @@ FROM gitpod/workspace-full
 USER root
 
 RUN bash -c ". /home/gitpod/.sdkman/bin/sdkman-init.sh && \
-    sdk install java 17.0.3-ms && \
-    sdk default java 17.0.3-ms"
+    sdk install java 21.0.1-tem && \
+    sdk default java 21.0.1-tem"
 
 # Install MySQL
 RUN install-packages mysql-server \