[GRASS-git] [OSGeo/grass-addons] af95a2: Reduce build matrix, remove Python 3.10 (#647)

[Vaclav Petras]

  Branch: refs/heads/grass8
  Home:   https://github.com/OSGeo/grass-addons
  Commit: af95a23ea1e73b86a18be5f4a5220db0e4fd8eb4
      https://github.com/OSGeo/grass-addons/commit/af95a23ea1e73b86a18be5f4a5220db0e4fd8eb4
  Author: Vaclav Petras <wenzeslaus at gmail.com>
  Date:   2021-12-21 (Tue, 21 Dec 2021)

  Changed paths:
    M .github/workflows/ci.yml

  Log Message:
  -----------
  Reduce build matrix, remove Python 3.10 (#647)

* Replace full matrix with all combinations of Python version and GRASS version by hand-picked combinations.
* Replace Python 3.10 by 3.7 in the matrix because of failing GDAL package install in 3.9 and 3.10.

In the future, tags or other branches can be added more freely without introducing multiple new jobs.
New Python versions can be tested with recent GRASS versions without interfering with old GRASS versions.
Multiple Python versions can still be tested (with a reduced number of jobs), although not in combination
with all GRASS versions.