PAF capitalization is weird in the assignment activity

[wes-otf]

When the PAF is assigned to a user, the activity message in the communications tab says pAF assigned to...

I think this stems from activity_feed.py but in my brief look nothing jumped out at me as wrong

Screenshots

[frjo]

I have created a PR that rename the last of "PAF" (hopefully) to "project form".

Let's see if that fixes the capitalisation as well.