You could do this if you want. The first question is how long a video do you want to produce? To make it look smooth, best to have about 25 or 30 frames per second.
So if you want a 1 minute video, you would need 1800 photos. Which means taking 60 photos per minute for 30 minutes, or 1 photo per second. So you can set your GoPro to record this.
Also depends on what you are recording in the timelapse. ie what is actually changing or moving. Some of the most impressive landscape timelapses feature changes in the weather, or clouds moving across the sky. In many places the weather can change dramatically in 30 minutes. But in other places the weather is more static, so a longer timelapse would be more interesting.