Update src/settings.rs

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

Author: NoodleSamaChan

src/settings.rs

@@ -218,16 +218,11 @@ impl Settings {
 
     #[must_use]
     pub fn with_distinct_attribute(self, distinct_attribute: Option<impl AsRef<str>>) -> Settings {
-        if let Some(distinct_attribute) = distinct_attribute {
-            Settings {
-                distinct_attribute: Some(Some(distinct_attribute.as_ref().to_string())),
-                ..self
-            }
-        } else {
-            Settings {
-                distinct_attribute: Some(None),
-                ..self
-            }
+        Settings {
+            distinct_attribute: Some(distinct_attribute.map(|distinct| distinct.to_string())),
+            ..self
+        }
+
         }
     }