Merge branch 'fix-assigned-issuable-lists' into 'master'

Add issuable-list class to shared mr/issue lists to fix new responsive layout

See merge request !12591

app/views/shared/_issues.html.haml

 - if @issues.to_a.any?
   .panel.panel-default.panel-small.panel-without-border
-    %ul.content-list.issues-list
+    %ul.content-list.issues-list.issuable-list
       = render partial: 'projects/issues/issue', collection: @issues
   = paginate @issues, theme: "gitlab"
 - else

app/views/shared/_merge_requests.html.haml

 - if @merge_requests.to_a.any?
   .panel.panel-default.panel-small.panel-without-border
-    %ul.content-list.mr-list
+    %ul.content-list.mr-list.issuable-list
       = render partial: 'projects/merge_requests/merge_request', collection: @merge_requests
 
   = paginate @merge_requests, theme: "gitlab"

changelogs/unreleased/fix-assigned-issuable-lists.yml

+---
+title: Add issuable-list class to shared mr/issue lists to fix new responsive layout
+  design
+merge_request:
+author: