Implement BinaryTypeDateTimeSub in type_traits

`CHAR_OCTET_LENGTH`: The maximum length in bytes of a character or binary data type column. For all other data types, this column returns a `NULL`.

AC:

- implement `BinaryDateTimeSub, SqlTypeDateTimeSub` under namespace `type_traits`
- call the function in `ColumnMetadataQuery::GetColumn` under case `ResultColumn::CHAR_OCTET_LENGTH`

https://docs.microsoft.com/en-us/sql/odbc/reference/syntax/sqlcolumns-function?view=sql-server-ver15

Locate the type_traits definitions for BinaryDateTimeSub and SqlTypeDateTimeSub, then inspect ColumnMetadataQuery::GetColumn and its ResultColumn::CHAR_OCTET_LENGTH case. Compare the implementation with the linked SQLColumns documentation; done means both functions are implemented and the case calls the appropriate function.

Written by the indexing model from the issue text.