Socket server code doesn't compile or run

### Type of issue

Typo

### Description

The socket server c# code on this page doesn't compile or run

### Page URL

https://learn.microsoft.com/en-us/dotnet/fundamentals/networking/sockets/socket-services

### Content source URL

https://github.com/dotnet/docs/blob/main/docs/fundamentals/networking/sockets/socket-services.md

### Document Version Independent Id

7f7bab6f-3aa6-8755-a541-a6c3b0121f1c

### Platform Id

8b232d70-f1c0-8dd8-4d8b-c56d35fff1ba

### Article author

@IEvangelist

### Metadata

* ID: 8918b064-85a6-4644-ecf7-aac48386c58d
* PlatformId: 8b232d70-f1c0-8dd8-4d8b-c56d35fff1ba
* Service: **dotnet-fundamentals**

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