Docs: Update plugin headers example in get_plugin_data() to clarify…

… that `Version` is not a required field.

Props casiepa.
See #47110, #meta4707.

git-svn-id: https://develop.svn.wordpress.org/trunk@45916 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/plugin.php

@@ -15,14 +15,14 @@
  * and the same goes for the plugin data. The below is formatted for printing.
  *
  *     /*
- *     Plugin Name: Name of Plugin
- *     Plugin URI: Link to plugin information
- *     Description: Plugin Description
- *     Author: Plugin author's name
- *     Author URI: Link to the author's web site
- *     Version: Must be set in the plugin for WordPress 2.3+
+ *     Plugin Name: Name of the plugin.
+ *     Plugin URI: The home page of the plugin.
+ *     Description: Plugin description.
+ *     Author: Plugin author's name.
+ *     Author URI: Link to the author's website.
+ *     Version: Plugin version.
  *     Text Domain: Optional. Unique identifier, should be same as the one used in
- *          load_plugin_textdomain()
+ *          load_plugin_textdomain().
  *     Domain Path: Optional. Only useful if the translations are located in a
  *          folder above the plugin's base path. For example, if .mo files are
  *          located in the locale folder then Domain Path will be "/locale/" and