Removes Merge Request reference from commit column due to performance issues

app/views/projects/deployments/_commit.html.haml

@@ -9,10 +9,6 @@
     = custom_icon("icon_commit")
   = link_to deployment.short_sha, namespace_project_commit_path(@project.namespace, @project, deployment.sha), class: "commit-id monospace"
 
-  - if merge_request
-    %span in
-    = link_to_gfm merge_request.to_reference, merge_request_path(merge_request)
-
   %p.commit-title
     %span
       - if commit_title = deployment.commit_title