change pub(super) enum to pub enum (#926)

Co-authored-by: cuihao <[email protected]>

utoipa-gen/src/lib.rs

@@ -2918,7 +2918,7 @@ mod parse_utils {
 
     #[derive(Clone)]
     #[cfg_attr(feature = "debug", derive(Debug))]
-    pub(super) enum Str {
+    pub enum Str {
         String(String),
         IncludeStr(TokenStream),
     }