MAGETWO-91521: Reports / Sales / Tax report show incorrect amount

- Update automated test according to comments

Author: lusinehak

app/code/Magento/Tax/Test/Mftf/Test/AdminTaxReportGridTest.xml

@@ -215,7 +215,7 @@
                 <argument name="taxClassName" value="TaxClasses2"/>
             </actionGroup>
 
-            <amOnPage url="admin/admin/auth/logout/" stepKey="amOnLogoutPage"/>
+            <actionGroup ref="logout" stepKey="logout"/>
          </after>
     </test>
 </tests>