[GRASS-git] [OSGeo/grass] 60959c: CI(deps): Update alpine Docker tag to v3.18

[renovate[bot]]

  Branch: refs/heads/renovate/alpine-3.x
  Home:   https://github.com/OSGeo/grass
  Commit: 60959cb7b70307d43b3ae924ab40b12788277334
      https://github.com/OSGeo/grass/commit/60959cb7b70307d43b3ae924ab40b12788277334
  Author: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
  Date:   2023-06-03 (Sat, 03 Jun 2023)

  Changed paths:
    M docker/alpine/Dockerfile

  Log Message:
  -----------
  CI(deps): Update alpine Docker tag to v3.18