fix highlight on new keyword

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Author: BillWagner

docs/csharp/programming-guide/types/index.md

@@ -139,7 +139,7 @@ char c = 'Z';
  All enums inherit from <xref:System.Enum?displayProperty=fullName>, which inherits from <xref:System.ValueType?displayProperty=fullName>. All the rules that apply to structs also apply to enums. For more information about enums, see [Enumeration Types](../../../csharp/programming-guide/enumeration-types.md).  
 
 ### Reference Types  
- A type that is defined as a [class](../../../csharp/language-reference/keywords/class.md), [delegate](../../../csharp/language-reference/keywords/delegate.md), array, or [interface](../../../csharp/language-reference/keywords/interface.md) is a *reference type*. At run time, when you declare a variable of a reference type, the variable contains the value [null](../../../csharp/language-reference/keywords/null.md) until you explicitly create an instance of the object by using the [new](../../../csharp/language-reference/keywords/new.md) operator, or assign it an object that has been created elsewhere by using `new, as shown in the following example:`  
+ A type that is defined as a [class](../../../csharp/language-reference/keywords/class.md), [delegate](../../../csharp/language-reference/keywords/delegate.md), array, or [interface](../../../csharp/language-reference/keywords/interface.md) is a *reference type*. At run time, when you declare a variable of a reference type, the variable contains the value [null](../../../csharp/language-reference/keywords/null.md) until you explicitly create an instance of the object by using the [new](../../../csharp/language-reference/keywords/new.md) operator, or assign it an object that has been created elsewhere by using `new`, as shown in the following example:
 
 ```csharp  
 MyClass mc = new MyClass();