Third-party Java OpenAI SDK is outdated, recommend replacing with a different SDK address

[alifsaputrahakim]

gateway/.github/README.cn.md

Line 175 in b93034c

| Java | [openai-java](https://github.com/TheoKanning/openai-java) |

gateway/.github/README.jp.md

Line 109 in b93034c

| Java | [openai-java](https://github.com/TheoKanning/openai-java) |

This outdated project currently has a maintained fork at https://github.com/Lambdua/openai4j. It's recommended to update the markdown to make it easier for Java users to integrate with.

[narengogi]

thanks for the headsup @alifsaputrahakim
cc: @siddharthsambharia-portkey