Check XML file with BOM is handled by xml2js

[bijujoseph]

xml2js - is the xml parsing library we use.
Unit test XMLs, JSON esp with BOM to make sure the parser library we use, support that properly.
BOM usually appears in files that are generated by some 3rd party libraries. You generate a test XML file by padding BOM in some editors.

Example scenario: Dr. Charlie downloaded his file from Registry website.

[samskeller]

I think it'd be preferable if you can strip this out before passing along to this module -- as the module accept QPP XML, which doesn't use a BOM

[bijujoseph]

See the comment here : #1 (comment)
i am under the impression that XML parsing is getting handled at server side on /submissions/validate endpoint
Should we instruct all API integrators (not just his client) to use XML without BOM or should we do a more robust server-side solution? cc: @shaselton , @lucasmbrown-usds
BTW this is not affecting our integration at the moment, that is why I did not assign this issue to anyone, but this is something in general that we must think through.