How do I expand my High Sierra partition to take up my entire SSD?

I just migrated my High Sierra installation from a ~750GB HDD to a 2TB SSD using Clonezilla. I thought I selected the option to have the partition on the target drive fill the entire drive, but apparently that didn't happen as Disk Utility is showing that my High Sierra partition is 749.3GB and there's 1.3TB of free space on the drive. It's not letting me expand the HFS partition to fill the rest of the drive, so is there a different tool I can use to expand the partition to take up the whole drive? Thanks!