Issue: MacBook Pros running Sierra or High Sierra restart when the computer goes to sleep.
This problem appears to be much more than a settings issue, but rather an issue common after OS X Sierra was released. At this point in time, there are suggested workarounds, but nothing concrete that can solve the issue. I will provide an update once this issue has a solution.
UPDATE 11/17/17
One suggested workaround is to do the following:
1. Go into your Settings.
2. Select Energy Saver
3. Make sure to deselect "Put hard disks to sleep when possible" and "Enable Power Nap while on battery power." This should be deselected in both Battery and Power Adapter. 
I have personally tested this and found it to work.
For more information on the technical side of things, follow this link: https://www.jamf.com/jamf-nation/discussions/24990/macbook-pro-s-shutting-down-in-sleep