Wp-calypso: Allow self purchased premium theme deletion

[cecilearkay]

As of now, users who wish to delete their site can't if they have a premium theme that they once purchased for their site. To delete their site, they first need to contact us so we can manually remove the site from the SA.

I'm hoping we can add a self-deletion option in Me > Manage Purchases.

Steps to reproduce

1. Starting at URL: https://wordpress.com/themes/
2. With some credits, purchase a premium theme for a free site.
3. Go to My Site > Settings > General > Delete site to delete the site. You'll be prompted with a message preventing you from deleting the site:
   
4. Go to Me > Manage Purchases and select the theme upgrade. The theme cannot be canceled and removed:
   

What I expected

To be able to delete the theme, so I can later delete my site.

What I'm suggesting

We could replace the "Renews on" part which isn't necessary (it already says "one-time" in the price box, so it's redundant) with a button to delete the theme. The user would then be prompted with a confirmation box with a message that let them know it can't be undone.

[melanieharari]

Related: https://github.com/Automattic/wp-calypso/issues/27014

[melanieharari]

May be the same issue as described here: https://github.com/Automattic/wp-calypso/issues/17012

[cecilearkay]

Sorry, those didn't come up when I did a search of close/open issues!

[melanieharari]

No worries! I was just digging through things to see if we're already tracking this somewhere, since it seems important

[KokkieH]

May be the same issue as described here: #17012

Technically, this is a duplicate of #9639, but that was closed in favour of #17012 to simply allow deletion of a site with Premium Themes, rather than adding the ability to cancel a premium theme - it's unlikely that someone would want to cancel a premium theme without wanting to delete their site.

Closing this issue as a duplicate, but this is also being worked on in #27917