Remove borders from option group [ci skip]

Signed-off-by: Matt Friedman <[email protected]>

adm/style/manage_ads.html

@@ -89,7 +89,7 @@ <h3>{{ lang('WARNING') }}</h3>
 					{% for location in loops.ad_locations %}
 						{% if location.CATEGORY_NAME %}
 							{% if not loop.first %}</optgroup>{% endif %}
-							<optgroup label="{{ location.CATEGORY_NAME }}">
+							<optgroup label="{{ location.CATEGORY_NAME }}" style="border:none;">
 						{% else %}
 							<option value="{{ location.LOCATION_ID }}"{% if location.S_SELECTED %} selected{% endif %} title="{{ location.LOCATION_DESC }}">{{ location.LOCATION_NAME }}</option>
 						{% endif %}