anchor.diff:   * PG_MASTER_USER -  database user account to use when checking the database
      using pg_isready utility
    * PG_DATABASE - database to use when checking the database using pg_isready
  - * REPLICA_TO_TRIGGER_LABEL - this is the pod name of a replica that you
  + * SLAVE_TO_TRIGGER_LABEL - this is the pod name of a replica that you
      want to choose as the new master in a failover, this will override
      the normal replica selection
   
  
positive.code:  * PG_USERNAME - user to connect to PostgreSQL
   * PG_PASSWORD - user password to connect to PostgreSQL
   * PG_MASTER_SERVICE_NAME - database host to connect to for the master node
   * PG_REPLICA_SERVICE_NAME - database host to connect to for the replica node
  
  === Features
  
  
negative.code: 
  === Environment Variables
  
   * PG_MODE - either *master*, *slave* or *set*, this value determines whether
     the database is set up as a master or replica instance, in the
     case of *set*, it means the container is started within a StatefulSet
     in a Kubernetes cluster.
  