fix broken string interpolation

app/views/projects/commit/_change.html.haml

@@ -13,7 +13,7 @@
         %a.close{href: "#", "data-dismiss" => "modal"} ×
         %h3.page-title== #{label} this #{commit.change_type_title(current_user)}
       .modal-body
-        = form_tag send("#{type.underscore}_namespace_project_commit_path", @project.namespace, @project, commit.id), method: :post, remote: false, class: 'form-horizontal js-#{type}-form js-requires-input' do
+        = form_tag send("#{type.underscore}_namespace_project_commit_path", @project.namespace, @project, commit.id), method: :post, remote: false, class: "form-horizontal js-#{type}-form js-requires-input" do
           .form-group.branch
             = label_tag 'target_branch', target_label, class: 'control-label'
             .col-sm-10