Add option to specify the path of the error file

[RatserX]

This change enables the use of the -e option for bcp (https://learn.microsoft.com/en-us/sql/tools/bcp-utility?view=sql-server-ver16#-e-err_file). This allows the creation of error files that contain detailed information about the rows that the bcp command couldn't process for whatever reason when executed.

Also included is a change to the bcp_path param typing to add the pathlib.Path type just because the bcp() function already allows it.