Resize Disk in Hyper-V for Linux Client

Shutdown Linux system.

Under System Settings in Hyper-V, select Edit disk and enlarge the capacity.

While system is off, add Gparted live disk to dvd and set dvd to be first boot option.
Start system.

In Gparted, double click the last active partition. Expand into available space as needed. Click the apply checkmark to resize.

Remove live image from dvd and reboot.