Warn that the SQLite backup feature doesn't produce a complete backup

Also add a link to the wiki page on backups.

src/static/templates/admin/settings.hbs

@@ -116,7 +116,11 @@
                             data-target="#g_database">Backup Database</button></div>
                     <div id="g_database" class="card-body collapse" data-parent="#config-form">
                         <div class="small mb-3">
-                            NOTE: A local installation of sqlite3 is required for this section to work.
+                            WARNING: This function only creates a backup copy of the SQLite database.
+                            This does not include any configuration or file attachment data that may
+                            also be needed to fully restore a bitwarden_rs instance. For details on
+                            how to perform complete backups, refer to the wiki page on
+                            <a href="https://github.com/dani-garcia/bitwarden_rs/wiki/Backing-up-your-vault">backups</a>.
                         </div>
                         <button type="button" class="btn btn-primary" onclick="backupDatabase();">Backup Database</button>
                     </div>