Fix TradeWizardPriceController throwing exception

Price controller was throwing an exception upon percentage validation.
It worked well while creating offers in one market, but when switching
markets and creating a new offer it failed since it was using the
previous quote price. Thus, this resets the missing fields every time
we use the TradeWizzard.

apps/desktop/desktop/src/main/java/bisq/desktop/main/content/bisq_easy/components/PriceInput.java

@@ -195,6 +195,7 @@ private Model() {
 
         public void reset() {
             priceQuote.set(null);
+            priceString.set(null);
             market = null;
             isFocused = false;
             description.set(null);

apps/desktop/desktop/src/main/java/bisq/desktop/main/content/bisq_easy/trade_wizard/price/TradeWizardPriceController.java

@@ -72,6 +72,7 @@ public ReadOnlyObjectProperty<PriceSpec> getPriceSpec() {
     }
 
     public void reset() {
+        priceInput.reset();
         model.reset();
     }