[cmake] Use upstream METIS

Official repos are at https://github.com/KarypisLab.

• https://github.com/KarypisLab/METIS
• https://github.com/KarypisLab/GKlib

Our fork at https://gitlab.opengeosys.org/ogs/libs/metis may be obsolete now.

1. Feature description was added to the changelog
2. Tests covering your feature were added?