fix optional replicatio index in hrana (#687)

Author: MarinPostma

sqld/src/hrana/proto.rs

@@ -50,8 +50,8 @@ pub struct StmtResult {
     #[serde(with = "option_i64_as_str")]
     #[prost(sint64, optional, tag = "4")]
     pub last_insert_rowid: Option<i64>,
-    #[prost(uint64, tag = "5")]
-    pub replication_index: u64,
+    #[prost(uint64, optional, tag = "5")]
+    pub replication_index: Option<u64>,
 }
 
 #[derive(Serialize, prost::Message)]

sqld/src/hrana/result_builder.rs

@@ -238,7 +238,7 @@ impl QueryResultBuilder for SingleStatementBuilder {
                 rows: std::mem::take(&mut self.rows),
                 affected_row_count: std::mem::take(&mut self.affected_row_count),
                 last_insert_rowid: std::mem::take(&mut self.last_insert_rowid),
-                replication_index: self.last_frame_no.unwrap(),
+                replication_index: self.last_frame_no,
             }),
         }
     }