fix lint error

Signed-off-by: Justin Pflueger <justin.pflueger@fermyon.com>

src/request.rs

@@ -13,7 +13,7 @@ impl TryInto<VerificationRequest> for Option<&Bytes> {
     fn try_into(self) -> Result<VerificationRequest, Self::Error> {
         match self {
             None => Ok(Default::default()),
-            Some(b) if b.len() == 0 => Ok(Default::default()),
+            Some(b) if b.is_empty() => Ok(Default::default()),
             Some(b) => serde_json::from_slice::<VerificationRequest>(b).map_err(|e| e.into()),
         }
     }