MAGETWO-87775: Automate MFTF tests

- Added test to create product attribute from product

Author: kieuphan2406

dev/tests/acceptance/tests/functional/Magento/FunctionalTest/Catalog/Section/AdminProductAttributeGridSection.xml

@@ -10,5 +10,6 @@
         xsi:noNamespaceSchemaLocation="../../../../../../vendor/magento/magento2-functional-testing-framework/src/Magento/FunctionalTestingFramework/Page/etc/SectionObject.xsd">
     <section name="AdminProductAttributeGridSection">
         <element name="AttributeCode" type="text" selector="//td[contains(text(),'{{var1}}')]" parameterized="true"/>
+        <element name="createNewAttributeBtn" type="button" selector="button[data-index='add_new_attribute_button']"/>
     </section>
 </sections>

dev/tests/acceptance/tests/functional/Magento/FunctionalTest/Catalog/Section/AdminProductFormSection.xml

@@ -19,6 +19,7 @@
         <element name="contentTab" type="button" selector="//strong[@class='admin__collapsible-title']/span[text()='Content']"/>
         <element name="fieldError" type="text" selector="//input[@name='product[{{fieldName}}]']/following-sibling::label[@class='admin__field-error']" parameterized="true"/>
         <element name="priceFieldError" type="text" selector="//input[@name='product[price]']/parent::div/parent::div/label[@class='admin__field-error']"/>
+        <element name="addAttributeBtn" type="button" selector="#addAttribute"/>
     </section>
     <section name="ProductWYSIWYGSection">
         <element name="Switcher" type="button" selector="//select[@id='dropdown-switcher']"/>