public List<RegionConfig> getRegions() {
    if (regions == null) {
      regions = new ArrayList<>();
    }
    return regions;
  }
Gets the list of the sub regions
Currently, users can not create regions with sub regions using management v2 api.
This sub region list will be ignored when creating the region.

@return the list of the sub regions
geode-core/src/main/java/org/apache/geode/cache/configuration/RegionConfig.java