Fix typeset error.

Author: csyonghe

proposals/029-conditional.md

@@ -121,7 +121,6 @@ Vertex<hasNormal, hasColor> vertMain<bool hasNormal, bool hasColor>(VertexIn inp
 It is also possible to use different types for each optional field. For example, we can define a set of helper types as:
 
 ```slang
-```
 interface IConditional<T>
 {
     static const bool hasValue;
@@ -200,4 +199,4 @@ the support with `Optional<T>` allows the language to ensure all uses of conditi
 of the field.
 
 As of writing, conditional fields that affect the data layout of the type are not known to be supported in any major CPU
-programming languages.
+programming languages.