feat/Support .xlsm documents

[Starfox64]

Is your feature request related to a problem? Please describe. Unstructured supports most Excel file formats (xls, xlsx) but documents that include macros use the .xlsm extension and are not recognized by Unstructured.

Describe the solution you'd like Unstructured should be capable of ingesting xlsm files as if they were regular Excel files but without macro execution. My cursory research indicates that there are no differences with from regular Excel files besides the inclusion of macros.

Describe alternatives you've considered An alternative would be converting such files to xlsx before sending them to Unstructured but it would be nice if those could be ingested as is.

Additional context N/A