remove useless nested form from admin group edit form

app/views/admin/groups/edit.html.haml

@@ -30,27 +30,26 @@
   %fieldset
     %legend LDAP group settings
     %div.form-holder
-      = form_for @group do |f|
-        .form-group.clearfix
-          = f.label :ldap_cn, class: 'control-label' do
-            LDAP Group cn
-          .col-sm-10
-            = f.hidden_field :ldap_cn, placeholder: "Ex. QA group", class: "xxlarge ajax-ldap-groups-select input-mn-300"
-            .help-block
-              Synchronize #{@group.name}'s members with this LDAP group.
-              %br
-              If you select an LDAP group you do not belong to you will lose ownership of #{@group.name}.
+      .form-group.clearfix
+        = f.label :ldap_cn, class: 'control-label' do
+          LDAP Group cn
+        .col-sm-10
+          = f.hidden_field :ldap_cn, placeholder: "Ex. QA group", class: "xxlarge ajax-ldap-groups-select input-mn-300"
+          .help-block
+            Synchronize #{@group.name}'s members with this LDAP group.
+            %br
+            If you select an LDAP group you do not belong to you will lose ownership of #{@group.name}.
 
-        .form-group.clearfix
-          = f.label :ldap_access, class: 'control-label' do
-            LDAP Access
-          .col-sm-10
-            = f.select :ldap_access, options_for_select(UsersGroup.group_access_roles, @group.ldap_access)
-            .help-block
-              Default, minimum permission level for LDAP group members of #{@group.name}.
-              %br
-              You can manage permission levels for individual group members in the Members tab.
+      .form-group.clearfix
+        = f.label :ldap_access, class: 'control-label' do
+          LDAP Access
+        .col-sm-10
+          = f.select :ldap_access, options_for_select(UsersGroup.group_access_roles, @group.ldap_access)
+          .help-block
+            Default, minimum permission level for LDAP group members of #{@group.name}.
+            %br
+            You can manage permission levels for individual group members in the Members tab.
 
-    .form-actions
-      = f.submit 'Save changes', class: "btn btn-primary"
-      = link_to  'Cancel', admin_groups_path, class: "btn btn-cancel"
+  .form-actions
+    = f.submit 'Save changes', class: "btn btn-primary"
+    = link_to  'Cancel', admin_groups_path, class: "btn btn-cancel"