Add donation buttons to app details tab

[edward-ly]

Describe the solution you'd like
A new donation attribute is now available to be added to each Nextcloud app's appinfo/info.xml file. Based on these attributes, add buttons similar to the other Interact buttons in the app details tab that correspond to the app's Donate buttons in the app store.

Additional context
The attribute specification as well as an example UI from the web app store can be found in nextcloud/appstore#1452.
Similar issue: #47143