consumer(ticdc): fix a panic about csv header decode (#12192)

ref #12179

Author: wk989898

pkg/sink/codec/csv/csv_decoder.go

@@ -79,7 +79,7 @@ func NewBatchDecoder(ctx context.Context,
 		// check column name
 		idx := len(header) - len(tableInfo.Columns)
 		for i, col := range tableInfo.Columns {
-			if col.Name.O != header[idx+i] {
+			if col.Name.L != header[idx+i] {
 				log.Panic("check column name order failed", zap.Any("col", col.Name.O), zap.Any("header", header[idx+i]))
 			}
 		}

tests/integration_tests/csv_storage_basic/data/schema.sql

@@ -42,12 +42,12 @@ CREATE TABLE multi_data_type
 );
 
 CREATE TABLE multi_charset (
-	id INT,
-	name varchar(128) CHARACTER SET gbk,
-	country char(32) CHARACTER SET gbk,
-	city varchar(64),
+	`id` INT,
+	Name varchar(128) CHARACTER SET gbk,
+	`Country` char(32) CHARACTER SET gbk,
+	CITY varchar(64),
 	description text CHARACTER SET gbk,
-	image tinyblob,
+	`IMAGE` tinyblob,
 	PRIMARY KEY (id)
 ) ENGINE = InnoDB CHARSET = utf8mb4;
 
@@ -61,4 +61,4 @@ CREATE TABLE binary_columns
     t_mediumblob         MEDIUMBLOB,
     t_longblob           LONGBLOB,
     PRIMARY KEY (id)
-);
+);