How to add Mozilla Firefox language to library json

[jcushenan]

I have seen the notes here on Mozilla Firefox regarding language https://stealthpuppy.com/evergreen/issues/

How do I add this AppParam to a library json file? I am not sure what the syntax should be.

[aaronparker]

I'll have to update Invoke-EvergreenLibraryUpdate to support the -AppParams parameter