[BUG][aspnetcore] Resolve Discrepancy between build.bat/sh files and launchProfiles

Description

The build.bat and build.sh files mention the next to run command:
https://github.com/OpenAPITools/openapi-generator/blob/5b6b4c9d4829b57716741dc35b3f1033e5483784/modules/openapi-generator/src/main/resources/aspnetcore/3.0/build.bat.mustache#L8
https://github.com/OpenAPITools/openapi-generator/blob/5b6b4c9d4829b57716741dc35b3f1033e5483784/modules/openapi-generator/src/main/resources/aspnetcore/3.0/build.sh.mustache#L8

But the mentioned profile (--launch-profile web) does not exist anymore: launchSettings.json, only "IIS Express", "OpenAPI" and "Docker".

Suggest a fix

I would have already supplied a PR fixing it but wanted to speak about a possible refactoring before:
Instead of supplying the build.sh/.bat files I would just like to include the commands one would need to run in the README.md. With an explanation of which profiles there are.
And possibly also with an explanation of how to run it in production (see #12216)

Compare the aspnetcore/3.0 build.bat.mustache and build.sh.mustache files with Properties/launchSettings.json, focusing on the referenced launch profile. Review the generated README.md and the related production-running discussion in #12216; done means the generated instructions reference available profiles and clearly explain how to run the application.