When items are sold in `continue building`-mode it sometimes gives more money back

[tolik518]

When building a power-core it will cost 2700, but when you sell it, you get 3000 back - I guess that issue arose with #10

Same goes for building a second workshop (buy 1800/sell 2000) (and probably other blocks that I haven't tested)

[evanbowman]

Yeah, I broke the code when fixing a previous issue. Building a workshop gives you a discount on building new blocks, and when removing the salvage penalty, you could recover more coins than you spent. Fixed in a new release: https://github.com/evanbowman/skyland-beta/releases/tag/2023.3.27.0