Fixed encoding of sql strings and added a test for it

Signed-off-by: GuptaManan100 <manan@planetscale.com>

go/sqltypes/value.go

@@ -404,8 +404,12 @@ func encodeBytesSQL(val []byte, b BinWriter) {
 func BufEncodeStringSQL(buf *strings.Builder, val string) {
 	buf.WriteByte('\'')
 	for _, ch := range val {
+		if ch > 255 {
+			buf.WriteRune(ch)
+			continue
+		}
 		if encodedChar := SQLEncodeMap[ch]; encodedChar == DontEscape {
-			buf.WriteByte(byte(ch))
+			buf.WriteRune(ch)
 		} else {
 			buf.WriteByte('\\')
 			buf.WriteByte(encodedChar)

go/vt/sqlparser/parse_test.go

@@ -1162,6 +1162,9 @@ var (
 		// The last value specified is used.
 		input:  "create table foo (f timestamp null not null , g timestamp not null null)",
 		output: "create table foo (\n\tf timestamp not null,\n\tg timestamp null\n)",
+	}, {
+		// Tests unicode character §
+		input: "create table invalid_enum_value_name (\n\there_be_enum enum('$§!') default null\n)",
 	}, {
 		input: "alter vschema create vindex hash_vdx using hash",
 	}, {