chore: make cargo clippy happy

src/lib.rs

@@ -217,21 +217,16 @@ pub struct Sheet {
 
 /// Row to use as header
 /// By default, the first non-empty row is used as header
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Default, Clone, Copy)]
 #[non_exhaustive]
 pub enum HeaderRow {
     /// First non-empty row
+    #[default]
     FirstNonEmptyRow,
     /// Index of the header row
     Row(u32),
 }
 
-impl Default for HeaderRow {
-    fn default() -> Self {
-        HeaderRow::FirstNonEmptyRow
-    }
-}
-
 // FIXME `Reader` must only be seek `Seek` for `Xls::xls`. Because of the present API this limits
 // the kinds of readers (other) data in formats can be read from.
 /// A trait to share spreadsheets reader functions across different `FileType`s