[GRASS-git] [OSGeo/grass-addons] f4002b: contributing: Add instructions on unit tests (#916)

[Luís de Sousa]

  Branch: refs/heads/grass8
  Home:   https://github.com/OSGeo/grass-addons
  Commit: f4002b7c270f9fa3fbb5275b2247816fcb41027e
      https://github.com/OSGeo/grass-addons/commit/f4002b7c270f9fa3fbb5275b2247816fcb41027e
  Author: Luís de Sousa <luis.de.sousa at protonmail.ch>
  Date:   2023-07-14 (Fri, 14 Jul 2023)

  Changed paths:
    M CONTRIBUTING.md
    A doc/development/submitting/UNIT_TESTS.md

  Log Message:
  -----------
  contributing: Add instructions on unit tests (#916)

Friendly text expanded from notes in the first day of GRASS Community Meeting Prague 2023.