Merge branch 'abuango-office365-broken-link-fix' into 'master'

Update Guide for Microsoft Teams Notification Integration

See merge request gitlab-org/gitlab-ce!22423

app/models/project_services/microsoft_teams_service.rb

@@ -17,7 +17,7 @@ class MicrosoftTeamsService < ChatNotificationService
     'This service sends notifications about projects events to Microsoft Teams channels.<br />
     To set up this service:
     <ol>
-      <li><a href="https://msdn.microsoft.com/en-us/microsoft-teams/connectors">Getting started with 365 Office Connectors For Microsoft Teams</a>.</li>
+      <li><a href="https://docs.microsoft.com/en-us/microsoftteams/platform/concepts/connectors/connectors-using#setting-up-a-custom-incoming-webhook">Setup a custom Incoming Webhook using Office 365 Connectors For Microsoft Teams</a>.</li>
       <li>Paste the <strong>Webhook URL</strong> into the field below.</li>
       <li>Select events below to enable notifications.</li>
     </ol>'