revert skin trials (#3293)

## Description:

Skin trials has been a failure, very low fill rate and cause a major
drop in sales.

reverts 


https://github.com/openfrontio/OpenFrontIO/commit/97d0a05d58e926e3de4ba46d8dd14a04d60d6698

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

evan

src/client/graphics/layers/WinModal.ts

@@ -204,7 +204,6 @@ export class WinModal extends LitElement implements Layer {
               .pattern=${pattern}
               .colorPalette=${colorPalette}
               .requiresPurchase=${true}
-              .allowTrial=${false}
               .onSelect=${(p: Pattern | null) => {}}
               .onPurchase=${(p: Pattern, colorPalette: ColorPalette | null) =>
                 handlePurchase(p, colorPalette)}