Render FormData content in console

[JakeUrban]

FormData objects do not provide a method for retrieving key-value pairs previously appended to them. .toString() does not work if binary data was appended, which is the only time FormData is used.

Its not immediately clear how we can render a string representation of the data encoded in the console when a test fails and the network calls are printed to the console.

https://github.com/form-data/form-data