MDL-58464 block_myoverview: remove additional placeholder in timeline

Remove the additional placeholder image when the user is not enrolled in
any courses from the sort by courses view in the timeline because there
is already a check for no in progress courses.

blocks/myoverview/templates/timeline-view-courses.mustache

@@ -57,14 +57,6 @@
                 <p class="text-muted m-t-1">{{#str}} nocoursesinprogress, block_myoverview {{/str}}</p>
             </div>
         {{/inprogress}}
-        {{^hascourses}}
-            <div class="text-xs-center text-center m-t-3">
-                <img class="empty-placeholder-image-lg"
-                     src="{{urls.noevents}}"
-                     alt="{{#str}} nocoursesinprogress, block_myoverview {{/str}}">
-                <p class="text-muted m-t-1">{{#str}} nocoursesinprogress, block_myoverview {{/str}}</p>
-            </div>
-        {{/hascourses}}
     {{/coursesview}}
 </div>
 {{#js}}