FIX: Cargo clippy. Manual fixes

xlsx/src/export/escape.rs

@@ -78,7 +78,7 @@ impl Extend<(usize, Value)> for Process<'_> {
 /// The resulting string is safe to use inside XML attribute values.
 ///
 /// Does not perform allocations if the given string does not contain escapable characters.
-pub fn escape_xml(s: &str) -> Cow<str> {
+pub fn escape_xml(s: &'_ str) -> Cow<'_, str> {
     let mut p = Process::Borrowed(s);
     p.extend(s.char_indices().map(|(ind, c)| (ind, escape_char(c))));
     p.into_result()