Fix documentation for BulkInsert

[OssiGalkin]

Documentation says "All object property names need to match with the destination table column names."

Looking from code it just uses https://docs.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlbulkcopy?view=dotnet-plat-ext-5.0

It won't use column mappings, which afaik should be used if column names would have any effect.

"If the data source and the destination table have the same number of columns, and the ordinal position of each source column within the data source matches the ordinal position of the corresponding destination column, the ColumnMappings collection is unnecessary. However, if the column counts differ, or the ordinal positions are not consistent, you must use ColumnMappings to make sure that data is copied into the correct columns." https://docs.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlbulkcopy.columnmappings?redirectedfrom=MSDN&view=dotnet-plat-ext-5.0#System_Data_SqlClient_SqlBulkCopy_ColumnMappings

-> check if instead of names, the amount and order needs to match and fix documentation if needed