Bug 1705980: trim tag spaces when creating post

After pressing New entry from a
Tagged journal entry block

behatnotneeded

Change-Id: Idb236e5d3bc5a10ab00f8a31f91da02ea8d4f606

htdocs/artefact/blog/post.php

@@ -39,7 +39,7 @@ if (!$blogpost) {
 
     $title = '';
     $description = '';
-    $tags = explode(",", $tagselect);
+    $tags = array_map('trim', explode(",", $tagselect));
     $checked = '';
     $pagetitle = get_string('newblogpost', 'artefact.blog', get_field('artefact', 'title', 'id', $blog));
     $focuselement = 'title';