clear input fields if product's not found

app/src/main/java/org/foxarmy/barcodescannerforemployees/activities/AddAbstractProductActivity.kt

@@ -201,6 +201,8 @@ class AddAbstractProductActivity : AppCompatActivity() {
                 runOnUiThread {
                     Toast.makeText(this, getString(R.string.no_product_in_online_database), Toast.LENGTH_LONG)
                         .show()
+                    productNameText.setText("")
+                    netWeightText.setText("")
                 }
                 return@thread
             }