style: Fix clippy warnings

Author: Pr0methean

src/write.rs

@@ -536,10 +536,10 @@ impl FileOptions<'_, ExtendedFileOptions> {
     /// Removes the extra data fields.
     #[must_use]
     pub fn clear_extra_data(mut self) -> Self {
-        if self.extended_options.extra_data.len() > 0 {
+        if !self.extended_options.extra_data.is_empty() {
             self.extended_options.extra_data = Arc::new(vec![]);
         }
-        if self.extended_options.central_extra_data.len() > 0 {
+        if !self.extended_options.central_extra_data.is_empty() {
             self.extended_options.central_extra_data = Arc::new(vec![]);
         }
         self