Correct indentation for issues/merge_requests partial render

Prior, it would only be shown if the issue had been edited.

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

@@ -46,8 +46,8 @@
           Edited
           = time_ago_with_tooltip(@issue.updated_at, placement: 'bottom', html_class: 'issue_edited_ago')
 
-        .merge-requests
-          = render 'merge_requests'
+      .merge-requests
+        = render 'merge_requests'
 
     .content-block
       = render 'votes/votes_block', votable: @issue
@@ -57,4 +57,4 @@
         .issuable-discussion
           = render 'projects/issues/discussion'
 
-= render 'shared/issuable/sidebar', issuable: @issue
+= render 'shared/issuable/sidebar', issuable: @issue