fix(codegen): Fixes codegenning timers when they are null. (#723)

When a timer is null, the code generator will use `TimeSpan.MinValue` as the delay.

Projects/Server/NativeReader.cs

@@ -57,6 +57,6 @@ namespace Server
             InternalRead(source, buffer, bufferIndex, length);
 
         internal unsafe int InternalRead(FileStream source, void* buffer, int bufferIndex, int length) =>
-            UnsafeNativeMethods.read(source.SafeFileHandle.DangerousGetHandle(), (byte*)buffer + bufferIndex, length);
+            UnsafeNativeMethods.read(source.SafeFileHandle!.DangerousGetHandle(), (byte*)buffer + bufferIndex, length);
     }
 }