fix md formatting

Author: RexJaeschke

standard/expressions.md

@@ -2512,7 +2512,7 @@ If *primary_no_array_creation_expression* is a writable variable, the result of
 public ref T this[int index] { get; }
 ```
 
-with *argument* as the index, on an instance of `System.Span<T>` that was created from the inline array designated by *primary_no_array_creation_expression*. For the purpose of ref-safety analysis, the safe-context ([§9.7.2.1]variables.md#9721-general)) of the access is equivalent to that for an invocation of a method with the signature
+with *argument* as the index, on an instance of `System.Span<T>` that was created from the inline array designated by *primary_no_array_creation_expression*. For the purpose of ref-safety analysis, the safe-context ([§9.7.2.1](variables.md#9721-general)) of the access is equivalent to that for an invocation of a method with the signature
 
 ```csharp
 static ref T GetItem(ref «InlineArrayType» array)