"The previous example assumes your project has an App.config file as shown below." Incorrect

### Type of issue

Code doesn't work

### Description

[Enter feedback here]
The line "The previous example assumes your project has an App.config file as shown below." is incorrect. You do not need such a file. It is ignored. A file assemblyname.dll.config is genrated at runtime in the runtime folder.

### Page URL

https://learn.microsoft.com/en-us/dotnet/api/system.configuration.configurationmanager.appsettings?view=net-8.0&viewFallbackFrom=windowsdesktop-8.0%253fwt.mc_id%3Ddt-mvp-5000301

### Content source URL

https://github.com/dotnet/dotnet-api-docs/blob/main/xml/System.Configuration/ConfigurationManager.xml

### Document Version Independent Id

421d1a09-fc61-0e6e-da61-a47a820fb41a

### Article author

@dotnet-bot