refactor(aws-lambda): remove unused setHeadersToResult

[exoego]

setHeadersToResult was added in #2657 but seems not used.

@yiss Please confirm it should be deleted or called.
If it should be called, I'll add tests and fix implementation.

The author should do the following, if applicable

• Add tests
• Run tests
• bun run format:fix && bun run lint:fix to format the code

[yiss]

Hi @exoeg, it should be called. Let me just check quickly if I forgot something in my PR

[yiss]

Yeah it seems that I forgot to remove it. LGTM the code of this function is handled by :

res.headers.forEach((value, key) => {
      result.headers[key] = value
      if (event.multiValueHeaders && result.multiValueHeaders) {
        result.multiValueHeaders[key] = [value]
      }
    })

[yusukebe]

@exoego @yiss Thanks both. Merging now.