Remove leading space from unordered list item prefix

[m417z]

Yet another fix for bullets. After my previous PR, the bullets prefix was reverted to the default value ' * ', and Discord treated it as sub-bullet.

Here's how it looks:

<ul><li>one</li><li>two</li></ul>

Turns into:

 * one
 * two

And is shown as:

[synzen]

Thanks for the follow-up fix - looks great!