ssh: Fix response code for ssh/verify

builtin/logical/ssh/path_verify.go

@@ -65,7 +65,7 @@ func (b *backend) pathVerifyWrite(req *logical.Request, d *framework.FieldData)
 		return nil, err
 	}
 	if otpEntry == nil {
-		return nil, nil
+		return logical.ErrorResponse("OTP not found"), nil
 	}
 
 	// Delete the OTP if found. This is what makes the key an OTP.