[GRASS-git] [OSGeo/grass] 9019e6: CONTRIBUTING.md: improve commit message hint

[Markus Neteler]

  Branch: refs/heads/master
  Home:   https://github.com/OSGeo/grass
  Commit: 9019e6c2f22cf59c94c63abb0afca0637ba027dc
      https://github.com/OSGeo/grass/commit/9019e6c2f22cf59c94c63abb0afca0637ba027dc
  Author: Markus Neteler <neteler at gmail.com>
  Date:   2020-05-27 (Wed, 27 May 2020)

  Changed paths:
    M CONTRIBUTING.md

  Log Message:
  -----------
  CONTRIBUTING.md: improve commit message hint