[TypeScript Fetch] Default TypeScript fetch configuration to 3.6+ true

Created by: szTheory

Related to issue https://github.com/OpenAPITools/openapi-generator/issues/9973

Here is a PR that changes the default to true. There is one issue however. I'm not sure why it's not updating the value to true in the generated documentation at docs/generators/typescript-fetch.md as well. Any ideas?

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