Fix #11600: Bugnote direct links include mismatched parenthesis

In the bugnote direct links in the left column of the "Notes" section of
an issue page, the right parenthesis is part of the link but the left
parenthesis is not.

This patch removes the parenthesis entirely and instead uses the value
of $g_bugnote_link_tag as a prefix to the bugnote ID. This technique is
a subtle reminder to users of the syntax to use within bugnotes and bug
descriptions to refer to a particular bugnote.

bugnote_view_inc.php

@@ -154,7 +154,7 @@
 <tr class="bugnote" id="c<?php echo $t_bugnote->id ?>">
         <td class="<?php echo $t_bugnote_css ?>">
 		<?php if ( ON  == config_get("show_avatar") ) print_avatar( $t_bugnote->reporter_id ); ?>
-		<span class="small">(<a href="<?php echo string_get_bugnote_view_url($t_bugnote->bug_id, $t_bugnote->id) ?>" title="<?php echo lang_get( 'bugnote_link_title' ) ?>"><?php echo $t_bugnote_id_formatted ?>)</a></span><br />
+		<span class="small"><a href="<?php echo string_get_bugnote_view_url($t_bugnote->bug_id, $t_bugnote->id) ?>" title="<?php echo lang_get( 'bugnote_link_title' ) ?>"><?php echo htmlentities( config_get_global( 'bugnote_link_tag' ) ) . $t_bugnote_id_formatted ?></a></span><br />
 		<?php
 			echo print_user( $t_bugnote->reporter_id );
 		?>