Sample code does not compile; methods outside of class definition

### Type of issue

Typo

### Description

There are several methods including `public void CallStaticPrivateMethod()` that don't belong to a class and thus won't compile.

If the intent is to show that this code should be somewhere else, such as generated code, then a wrapper class of some sort should be provided so at least the sample code compiles.

### Page URL

https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.unsafeaccessorattribute?view=net-9.0&source=docs

### Content source URL

https://github.com/dotnet/dotnet-api-docs/blob/main/xml/System.Runtime.CompilerServices/UnsafeAccessorAttribute.xml

### Document Version Independent Id

d8b3e8e8-a5e1-1884-99f2-678cf6a77a45

### Platform Id

cbce44e6-89f0-7d37-b0fd-cb328dfbdd90

### Article author

@dotnet-bot