Investigate whether this plugin is still required

[nmfisher]

Per https://github.com/flutter/flutter/issues/13937#issuecomment-1258766459, Flutter now seems to have support for running plugin code in background isolates, which would render this plugin redundant.

This is apparently merged into Flutter master (not yet stable as of 12 November 2022) - I don't have much free time so would appreciate someone investigating further to see if this is correct.