added link target for bookmarks in tag usage list

frontend/src/routes/tags/Reference.svelte

@@ -36,7 +36,7 @@
 {#if module=='bookmark'}
 {@html target(object.comment.rendered).replace(/<p>(.*?)<\/p>/, '$1')} <!-- this is a workaround for in-proper formatting of paragraphs within list items in firefox -->
 <p>
-<a href={object.url}>{object.url}</a>
+<a href={object.url} target="_blank">{object.url}</a>
 </p>
 <hr/>
 {:else if module=='task' || module=='project'}