Update README.md

Author: DennisTraub

javav2/example_code/bedrock-runtime/README.md

@@ -17,6 +17,7 @@ _Amazon Bedrock Runtime is a fully managed service that makes it easy to use fou
 * This code is not tested in every AWS Region. For more information, see [AWS Regional Services](https://aws.amazon.com/about-aws/global-infrastructure/regional-product-services).
 
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+### Note: This project uses JDK 21
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 ## Code examples