Add content for gmail tester (#2888)

content/roadmaps/113-qa/content/105-qa-email-testing/101-gmail-tester.md

@@ -1 +1,8 @@
-# Gmail tester
+# Gmail Tester
+
+Gmail-tester is a simple Node.js Gmail client which checks/returns email message(s) straight from any Gmail-powered account (both private and company).
+
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink colorScheme='blue' badgeText='Official Website' href='https://www.npmjs.com/package/gmail-tester'>Gmail-tester Website</BadgeLink>
+<BadgeLink colorScheme='yellow' badgeText='Read' href='https://medium.com/@sergtimosh/using-gmail-tester-puppeteer-to-poll-gmail-inbox-65bbee17618c'>Using the gmail-tester + Puppeteer to poll Gmail inbox</BadgeLink>