fix(doc): fix md table syntax error

Signed-off-by: Jiyong Huang <huangjy@emqx.io>

docs/en_US/sqls/data_types.md

@@ -24,13 +24,13 @@ There may be binary operations in each sql clause. In this example, `Select temp
 
 Array and struct are not supported in any binary operations. The compatibility of other data types are listed in below table. Whereas, the row header is the left operand data type and the column header is the right operand data. The value is the compatibility in which Y stands for yes and N stands for no.
 
-| #        / bigint| float  | string                    | datetime| boolean |
-| -------- | ----- | ------ | ------------------------- | ------- | ------- /
-| bigint   | Y     | Y      | N                         | N       |  N      /
-| float    | Y     | Y      | N                         | N       |  N      /
-| string   | N     | N      | Y                         | N       |  N      /
-| datetime | Y     | Y      | Y, if in the valid format | Y       |  N      /
-| boolean  | N     | N      | N                         | N       |  Y      /
+| #       | bigint| float  | string                    | datetime| boolean |
+| -------- | ----- | ------ | ------------------------- | ------- | -------|
+| bigint   | Y     | Y      | N                         | N       |  N     |
+| float    | Y     | Y      | N                         | N       |  N     |
+| string   | N     | N      | Y                         | N       |  N     |
+| datetime | Y     | Y      | Y, if in the valid format | Y       |  N     |
+| boolean  | N     | N      | N                         | N       |  Y     |
 
  The default format for datetime string is ``"2006-01-02T15:04:05.000Z07:00"``
 

docs/zh_CN/sqls/data_types.md

@@ -24,13 +24,13 @@
 
 数组和结构在任何二元操作中均不受支持。 下表列出了其他数据类型的兼容性。 而行标题是左操作数数据类型，列标题是右操作数数据。 关于兼容性的值，其中 Y 表示是，N 表示否。
 
-| #        / bigint| float  | string                    | datetime| boolean |
-| -------- | ----- | ------ | ------------------------- | ------- | ------- /
-| bigint   | Y     | Y      | N                         | N       |  N      /
-| float    | Y     | Y      | N                         | N       |  N      /
-| string   | N     | N      | Y                         | N       |  N      /
-| datetime | Y     | Y      | Y, 如满足日期时间默认格式      | Y       |  N      /
-| boolean  | N     | N      | N                         | N       |  Y      /
+| #       | bigint| float  | string                    | datetime| boolean |
+| -------- | ----- | ------ | ------------------------- | ------- | -------|
+| bigint   | Y     | Y      | N                         | N       |  N     |
+| float    | Y     | Y      | N                         | N       |  N     |
+| string   | N     | N      | Y                         | N       |  N     |
+| datetime | Y     | Y      | Y, 如满足日期时间默认格式      | Y       |  N     |
+| boolean  | N     | N      | N                         | N       |  Y     |
 
 日期时间字符串的默认格式是 `"2006-01-02T15:04:05.000Z07:00"`