Add Expiration Date

[PatMurrayDEV]

What happens to the #VoteYes corner on 15 November 2017?

Do we remove all corners, or switch out to one of our generic pride corners?

[timacdonald]

What if you update it with "said yes" like: https://twitter.com/ALeighMP/status/935284225896431616

I'm really not sure why the vote yes corner is still up there in 2021