Fix typo and remove uneeded code

Author: Ecarrion

WooCommerce/Classes/ViewRelated/Orders/Simple Payments/Amount/SimplePaymentsAmount.swift

@@ -139,7 +139,6 @@ struct SimplePaymentsAmount: View {
                     dismiss()
                     viewModel.userDidCancelFlow()
                 })
-                    .disabled(viewModel.disableViewActions)
             }
         }
         .disabled(viewModel.disableViewActions)

WooCommerce/Classes/ViewRelated/Orders/Simple Payments/Amount/SimplePaymentsAmountViewModel.swift

@@ -35,7 +35,7 @@ final class SimplePaymentsAmountViewModel: ObservableObject {
     ///
     var onOrderCreated: (Order) -> Void = { _ in }
 
-    /// Returns true when amount is a valid number bigger than .zero.
+    /// Returns true when the amount is not a positive number.
     ///
     var shouldDisableDoneButton: Bool {
         let decimalAmount = (currencyFormatter.convertToDecimal(from: amount) ?? .zero) as Decimal