function for Deepgram's TopicDetection added

What does this PR do?

This PR adds the "deepgramTopicDetection" java function to openruntime java library as per the requirement of the issue

[x] Ask to be assigned to the issue.
[x] Implement function deepgramTopicDetection() in Java/ folder.
[x] Manually execute the newly implemented function to ensure it works.
[x] Submit a pull request in open-runtimes/examples and include screenshots of successful execution.