remove redundant comment regarding error handling; update comment for…

… barrier commit

src/connector/src/sink/snowflake.rs

@@ -365,6 +365,7 @@ impl SinkWriter for SnowflakeSinkWriter {
         if is_checkpoint {
             // finalize current streaming upload, plus notify snowflake to sink
             // the corresponding data to snowflake pipe.
+            // note: if no data needs to be committed, then `commit` is simply a no-op.
             self.commit().await?;
         }
         Ok(())

src/connector/src/sink/snowflake_connector.rs

@@ -203,9 +203,6 @@ impl SnowflakeS3Client {
         let config = ObjectStoreConfig::default();
 
         // create the s3 engine for streaming upload to the intermediate s3 bucket
-        // note: this will lead to an internal panic if any credential / intermediate creation
-        // process has error, which may not be acceptable...
-        // but it's hard to gracefully handle the error without modifying downstream return type(s)...
         let opendal_s3_engine = OpendalObjectStore::new_s3_engine_with_credentials(
             &s3_bucket,
             config,