Merge branch '5170-on-the-issue-list-add-tooltip-to-weight-value' into 'master'

Issues List: Add tooltip to weight icon

Closes #5170

See merge request gitlab-org/gitlab-ee!4935

app/views/projects/issues/_issue.html.haml

@@ -38,7 +38,7 @@
               = link_to_label(label, subject: issue.project, css_class: 'label-link')
 
           - if issue.weight
-            %span.issuable-weight
+            %span.issuable-weight.has-tooltip{ data: { container: 'body' }, title: _('Weight') }
                
               = icon('balance-scale')
               = issue.weight