It should be a bug in the latest package version, so downgrading can help until the issue is resolved:
sudo dnf downgrade gparted
Or use the following workaround to customize the launcher:
mkdir -p ~/.local/bin
tee ~/.local/bin/gparted << "EOF" > /dev/null
#!/usr/bin/bash
pkexec env DISPLAY="${DISPLAY}" \
XAUTHORITY="${XAUTHORITY}" /usr/bin/gparted "${@}"
EOF
chmod +x ~/.local/bin/gparted
desktop-file-install \
--dir=${HOME}/.local/share/applications \
--set-key=Exec \
--set-value="gparted %f" \
/usr/share/applications/gparted.desktop
It follows the XDG specification and should work across DEs, although you may need to relogin to apply changes.