fixed an issue when no postgis_version defined
fixed an issue when no postgis_version defined

AtlasOfLivingAustralia/ala-install,AtlasOfLivingAustralia/ala-install,AtlasOfLivingAustralia/ala-install,AtlasOfLivingAustralia/ala-install,AtlasOfLivingAustralia/ala-install