Fix two CI lint errors reported by clippy.

Signed-off-by: Gerd Zellweger <[email protected]>

src/datetime/tests.rs

@@ -403,7 +403,7 @@ fn signed_duration_since_autoref() {
     let dt1 = Utc.with_ymd_and_hms(2014, 5, 6, 7, 8, 9).unwrap();
     let dt2 = Utc.with_ymd_and_hms(2014, 3, 4, 5, 6, 7).unwrap();
     let diff1 = dt1.signed_duration_since(dt2); // Copy/consume
-    let diff2 = dt2.signed_duration_since(&dt1); // Take by reference
+    let diff2 = dt2.signed_duration_since(dt1); // Take by reference
     assert_eq!(diff1, -diff2);
 
     let diff1 = dt1 - &dt2; // We can choose to substract rhs by reference

src/format/scan.rs

@@ -306,7 +306,7 @@ where
     };
     s = match s.len() {
         len if len >= 2 => &s[2..],
-        len if len == 0 => s,
+        0 => s,
         _ => return Err(TOO_SHORT),
     };