fix(bidengine): decode script result directly into decint

Signed-off-by: Artur Troian <troian.ap@gmail.com>

bidengine/shellscript.go

@@ -185,15 +185,11 @@ func (ssp shellScriptPricing) CalculatePrice(ctx context.Context, req Request) (
 	decoder := json.NewDecoder(outputBuf)
 	decoder.UseNumber()
 
-	var priceNumber json.Number
-	err = decoder.Decode(&priceNumber)
-	if err != nil {
-		return sdk.DecCoin{}, fmt.Errorf("%w: script failure %s", err, stderrBuf.String())
-	}
+	valueStr := strings.TrimSpace(outputBuf.String())
 
-	price, err := sdk.NewDecFromStr(priceNumber.String())
+	price, err := sdk.NewDecFromStr(valueStr)
 	if err != nil {
-		return sdk.DecCoin{}, ErrBidQuantityInvalid
+		return sdk.DecCoin{}, fmt.Errorf("%w: unable to decode price from %s", err, valueStr)
 	}
 
 	if price.IsZero() {