File attachments allows MSI and JSON files to be uploaded despite not being in acceptedTypes

[Blackbaud-JeffDye]

Expected behavior

File attachments component would reject all files types except jpeg and png.

Actual behavior

.MSI and .JSON files can be uploaded freely (though most other file types are properly rejected).

Steps to reproduce

Upload an MSI or JSON file using the OS file selector or drag/drop one into the browser.

Plunker

https://plnkr.co/edit/0PIVgL8XGonfcMm5jst5?p=preview

[Blackbaud-PatrickOFriel]

I dont have an msi on hand to test this with, but it seems to be working fine with json in terms of rejecting files.

[Blackbaud-PatrickOFriel]

Investigating on Windows

[Blackbaud-PatrickOFriel]

Looks like windows doesn't have specify a type for all files. If a user specifies a type, and the OS does not provide type information for the file, we should reject the files. Right now if no type exists, we accept the files. I'll go ahead and do this update

[Blackbaud-PatrickOFriel]

In 2.0.0-beta.23