[typescript] Support esbuild, second attempt

[bodograumann]

The first try in #11298 did not work, because it broke the commonjs output.

Now I have differentiated between the two. When es6 is activated, we build an esmodule and when it is deactivated we build the classic commonjs format. For commonjs we don’t need to change our imports, because the esmodule import restrictions don’t apply to the commonjs format. For esmodule output we use a default import.

To make sure everything works, I have added a new sample that has supportsES6 enabled. The tests for it use esbuild as bundler. (Unfortunately a bundler is needed in any case, because we include commonjs polyfills. Ideally the esmodule output could just run in the browser as-is, but that is something for another day.)

As before I have included proper typings for url-parse.
I also had to expose the RequiredError exception type to allow explicit casting to it, because typescript regards errors in catch as unknown these days.
Pet API tests are run against http://localhost/v2 as base server, to prevent HSTS in the browser from forcing https.
Finally, I added more fields to package.json that include the module type and entry point, to improve compatibility with node and bundlers, especially when generating esmodule output.

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[bodograumann]

Ugh, seems pupeteer does not readily work in the pipeline:

/home/circleci/OpenAPITools/openapi-generator/samples/openapi3/client/petstore/typescript/tests/browser/node_modules/puppeteer/.local-chromium/linux-950341/chrome-linux/chrome: error while loading shared libraries: libgbm.so.1: cannot open shared object file: No such file or directory

I have added the chromium dependencies to circleci as per the pupeteer instructions. Hope this is the way to go.

[bodograumann]

Neither libgbm1 nor libgbm-dev can be installed :-|.
Is the ci base image too old @wing328 ?

[bodograumann]

Yay it works! 🚀

Please have another look at this PR now.

[macjohnny]

LGTM