[GRASS-git] [OSGeo/grass] a69150: Update gis.h

[Markus Metz]

  Branch: refs/heads/releasebranch_7_8
  Home:   https://github.com/OSGeo/grass
  Commit: a6915039d1b55313a0d1b00ebd8b1efd7f4dd0d4
      https://github.com/OSGeo/grass/commit/a6915039d1b55313a0d1b00ebd8b1efd7f4dd0d4
  Author: Markus Metz <33666869+metzm at users.noreply.github.com>
  Date:   2020-01-12 (Sun, 12 Jan 2020)

  Changed paths:
    M include/gis.h

  Log Message:
  -----------
  Update gis.h

GRASS_VERSION_STRING is a macro not a literal string