[REQ] [Typescript] Use `node:` Prefix-Only For Core Modules

Is your feature request related to a problem? Please describe.

Hi, I'm using the typescript generator with the deno platform.
Deno is now fully node compatible, but since some node native objects are imported implicitly, the generated code results in some errors.

For instance, Buffer is used in https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/typescript/auth/auth.mustache#L88 without any import, and Deno can't resolve it.

error: Uncaught (in promise) ReferenceError: Buffer is not defined
        let comb = Buffer.from(this.username + ":" + this.password, 'binary').toString('base64');
                   ^
    at BasicAuthAuthentication.applySecurityAuthentication (file:///home/project/auth/auth.ts:65:20)

Describe the solution you'd like

The solution is as easy as :

import { Buffer } from "node:buffer";

Disclaimer : this feature was introduced in node 18.

Describe alternatives you've considered

Use web API compliant code to encode to base64.

Additional context

Start with modules/openapi-generator/src/main/resources/typescript/auth/auth.mustache and inspect the TypeScript generator templates for other implicit Node core-module usage. Check how generated Deno clients handle these imports, then verify that the affected generated code uses node:-prefixed imports and no longer raises the reported Buffer error.