function getVersions() {
  // get all tags from git
  // "trim" is used to remove the ending new-line
  const res = childProcess.execSync('git tag').toString().trim();

  filteredTags = res.split('\n')
  // map all gotten tags if they match the regular expression
    .map(parseVersion)
  // filter out all null / undefined / falsy values
    .filter(v => !!v)
  // sort tags with latest (highest) first
    .sort((a, b) => {
      if (a[0] === b[0]) {
        if (a[1] === b[1]) {
          return b[2] - a[2];
        }
        return b[1] - a[1];
      }
      return b[0] - a[0];
    });

  if (filteredTags.length === 0) {
    console.error('no tags found!');
    filteredTags.push([0, 0, 0]);
  }
}
Get versions from git tags and put them into {@link filteredTags}