CTP-2241: add Behat test checking alert is displayed (#10)

* testing one alert
* checking link in alert

Co-authored-by: Matthias Opitz <[email protected]>

Author: opitz

tests/behat/show_alerts.feature

@@ -0,0 +1,23 @@
+@block @block_alerts
+Feature: Show alerts
+  In order to alert users
+  As a user
+  I need to be able to see that the alerts block shows the intended alert.
+
+  Background:
+    Given the following "blocks" exist:
+      | blockname   | contextlevel | reference  | pagetypepattern | defaultregion |
+      | alerts      | System       | 1          | site-index      | side-pre      |
+    And the following config values are set as admin:
+      | config                  | value                           | plugin        |
+      | title1                  | Alert Title One                 | block_alerts  |
+      | description1            | Alert Description One           | block_alerts  |
+      | link1                   | https://nasa.gov                | block_alerts  |
+      | linktext1               | Alert Link One                  | block_alerts  |
+
+  Scenario: See news as intended and check the links lead to the intended websites.
+    When I am on site homepage
+    Then I should see "Alert Title One"
+    And I should see "Alert Description One"
+    When I click on "Alert Link One" "link"
+    Then I should see "NASA"