Call WebApplication.CreateBuilder(args) only once

[tdykstra]

Fixes #34216

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aspnetcore/fundamentals/configuration/index.md	Configuration in ASP.NET Core

[Copilot]

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Comments suppressed due to low confidence (1)

aspnetcore/fundamentals/configuration/index.md:63

• [nitpick] The sentence could be rephrased for clarity: 'Although this article mentions WebApplication.CreateBuilder(args) multiple times, application code should call this method only once.'

> While this article mentions `WebApplication.CreateBuilder(args)` many times, application code should call this method only once.

[Rick-Anderson]

overreaction to one customer and too much bling. I'd change it to:
Do a search on WebApplication.CreateBuilder(args), all the code samples show it's only called once. This is not a recurrent problem.

NOTE:: WebApplication.CreateBuilder(args) should only be called once.

The 2nd time you call it
var builder = WebApplication.CreateBuilder(

you get a compiler error.
I'm not sure I'd even need a warn. We can't overreact to every error a customer makes and spam the topic with warnings.

[Copilot]

Copilot reviewed 1 out of 1 changed files in this pull request and generated no comments.

[Rick-Anderson]

Suggested change

Note: `WebApplication.CreateBuilder(args)` should only be called once.

Many of our docs use the same API many times, for example app.UseCors `https://learn.microsoft.com/en-us/aspnet/core/security/cors

[tdykstra]

The link we originally had here tells why you don't want to call this API multiple times but people tend to think it can or needs to be. Perhaps it would be good to put the link back in?
https://techcommunity.microsoft.com/blog/iis-support-blog/asp-net-core-503-server-has-been-shutdown/3830338

[Rick-Anderson]

Sure