Fixes clippy and fmt

src/handshake/certificate.rs

@@ -14,6 +14,7 @@ pub struct CertificateRef<'a> {
 }
 
 impl<'a> CertificateRef<'a> {
+    #[must_use]
     pub fn with_context(request_context: &'a [u8]) -> Self {
         Self {
             raw_entries: &[],
@@ -30,11 +31,15 @@ impl<'a> CertificateRef<'a> {
     }
 
     pub fn parse(buf: &mut ParseBuffer<'a>) -> Result<Self, ProtocolError> {
-        let request_context_len = buf.read_u8().map_err(|_| ProtocolError::InvalidCertificate)?;
+        let request_context_len = buf
+            .read_u8()
+            .map_err(|_| ProtocolError::InvalidCertificate)?;
         let request_context = buf
             .slice(request_context_len as usize)
             .map_err(|_| ProtocolError::InvalidCertificate)?;
-        let entries_len = buf.read_u24().map_err(|_| ProtocolError::InvalidCertificate)?;
+        let entries_len = buf
+            .read_u24()
+            .map_err(|_| ProtocolError::InvalidCertificate)?;
         let mut raw_entries = buf
             .slice(entries_len as usize)
             .map_err(|_| ProtocolError::InvalidCertificate)?;