[TypeScript] Fix type array with uniqueItems

[ty-v1]

resolve #10174.

This PR fixes typescript generator so that it does not generate import of Set when an array with uniqueItems exists.

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
• Run the following to build the project and update samples:

  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
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[macjohnny]

Thanks for your contribution!