Originally, this dummy declaration was needed because there was the possibility of the generated code doesn't use context.Context and then if it imported that package, go compiler complains that and makes an error.

ref:

However, now this dummy placement is no longer needed because the generated code always uses context.Context.
So this pull request removes that dummy declaration.

cc. @antihax @grokify @kemokemo @jirikuncar @ph4r5h4d

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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