Refactor code based on clippy suggestions

src/utils.rs

@@ -25,9 +25,11 @@ pub fn read_base64_lines(path: &str) -> Vec<Bytes> {
     let br = BufReader::new(file);
     br.lines()
         .map(|line| {
-            BytesBase64::from_base64(&line.expect(&format!("Failed to read line in {}", path)))
-                .expect(&format!("Invalid base64 in {}", path))
-                .to_bytes()
+            BytesBase64::from_base64(
+                &line.unwrap_or_else(|_| panic!("Failed to read line in {}", path)),
+            )
+            .unwrap_or_else(|_| panic!("Invalid base64 in {}", path))
+            .to_bytes()
         })
         .collect()
 }