Fix clippy warnings

pkcs11/src/backend/encrypt.rs

@@ -135,7 +135,7 @@ fn encrypt_data(
                     return Error::InvalidData;
                 }
             }
-            err.into()
+            err
         })?;
 
     Ok(Base64::decode_vec(&output.entity.encrypted)?)

pkcs11/src/backend/key.rs

@@ -486,7 +486,7 @@ fn fetch_one_key(
             ) {
                 return Ok(vec![]);
             }
-            return Err(err.into());
+            return Err(err);
         }
     };
 

pkcs11/src/backend/login.rs

@@ -364,6 +364,7 @@ fn get_user_api_config(
 ) -> Option<nethsm_sdk_rs::apis::configuration::Configuration> {
     let user = user?;
 
+    #[allow(clippy::question_mark)]
     if user.password.is_none() {
         return None;
     }