[Test] Add in unit test attempting to demonstrate issue caused by dev…

[seamuslee001]

…/core#1069

Overview

This updates our current unit test to include a situation where we are using the logged in contact's email address as the from email address by passing a numerical from_email_address param to the form submission

Before

No Test

After

Test

ping @yashodha @eileenmcnaughton is there anything else we need to be testing here? this is passing for me locally, i'm trying to nail down the exact steps to replicate

[civibot]

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[eileenmcnaughton]

Extends test cover