To add a horizontal line now you use the Borders menu.
The problem being that when you do add the line, there is a huge gap between the previous text and the line created.
The only solutions I found online were work-arounds like adding a shape or using a paragraph border. I HATE work-arounds like that. It doesn't solve the problem, it just uses something else. I want to know how to move that line up!
So, the real solution is to select the line, go into the Font menu, click the Advanced tab, and change the Position from Normal to Raised. Then, change the number of Points to raise the line by. At a 26 pt font I chose 18 pts.
Voila!
Now you can adjust the font size and the raised size of the line to get exactly the spacing you want.