ACQE-8712: [MFTF TESTS] StorefrontCreateOrderWithDifferentAddressesTest

- Added select flatrate method action group to fix the test failure

Author: pradyumnabhat9797

app/code/Magento/Sales/Test/Mftf/Test/StorefrontCreateOrderWithDifferentAddressesTest.xml

@@ -44,6 +44,7 @@
             <argument name="customer" value="$$createCustomer$$"/>
         </actionGroup>
 
+        <actionGroup ref="CheckoutSelectFlatRateShippingMethodActionGroup" stepKey="selectFlatRate"/>
         <actionGroup ref="StorefrontCheckoutClickNextOnShippingStepActionGroup" stepKey="gotoPaymentStep"/>
          <actionGroup ref="CheckoutSelectCheckMoneyOrderPaymentActionGroup" stepKey="selectCheckMoneyOrder"/>