Bump NodeInfo plugin version to 3.0.0

Updated the plugin version in nodeinfo.php from 2.3.1 to 3.0.0 to reflect a new release. No other changes were made.

Author: pfefferle

nodeinfo.php

@@ -3,7 +3,7 @@
  * Plugin Name: NodeInfo
  * Plugin URI: https://github.com/pfefferle/wordpress-nodeinfo/
  * Description: NodeInfo is an effort to create a standardized way of exposing metadata about a server running one of the distributed social networks.
- * Version: 2.3.1
+ * Version: 3.0.0
  * Author: Matthias Pfefferle
  * Author URI: https://notiz.blog/
  * License: MIT