Dump EDD license key.

dump-edd-key.php

<?php
    function fs_dump_edd_key() {
         if (is_admin()) {
            $license_key = trim( get_option( 'my_edd_license_key' ) );
            ?>
            <div class="notice notice-error is-dismissible">
                <p>license key <?php echo $license_key ?></p>
            </div>
            <?php
         }
    }
    add_action( 'admin_notices', 'fs_dump_edd_key' );