Show the correct user in Pulse page

The list of requests in the Pulse page was always showing the creator
instead of the user who performed the action (accept, revoke, etc.).

Now this is fixed and closes #8656

src/api/app/views/webui/projects/pulse/_pulse_list_requests.html.haml

@@ -7,11 +7,15 @@
       = link_to(request_show_path(request.number), title: request.description) do
         = request.number
       - if request.request_history_elements.any?
-        = request.request_history_elements.last.description.gsub('Request', '')
+        - history_element = request.request_history_elements.last
+        = history_element.description.gsub('Request', '')
+        by
+        = link_to(user_path(history_element.user)) do
+          = history_element.user
       - else
         was created
-      by
-      = link_to(user_path(request.creator)) do
-        = request.creator
+        by
+        = link_to(user_path(request.creator)) do
+          = request.creator
       = fuzzy_time(request.updated_at)