Styling issue settings page

Hello,

I noticed the tab of Bulk Discount is missing a span, which creates a styling issue in the admin. You could solve this by adding a span on line 583 in woocommerce-bulk-discount.php.

Current:
echo ‘<li class=”bulkdiscount_tab bulkdiscount_options”>‘ . __( ‘Bulk Discount’, ‘wc_bulk_discount’ ) . ‘‘;

http://prntscr.com/igt86k

Fix:
echo ‘<li class=”bulkdiscount_tab bulkdiscount_options”><span>’ . __( ‘Bulk Discount’, ‘wc_bulk_discount’ ) . ‘</span>‘;

http://prntscr.com/igt7ar

Good luck!