Upgrade to Postgres 10 on AWS RDS Confluence can't find tables

Issue Summary

This ticket is used to track a bug on RDS - after Postgres 10 upgrade, Confluence may fail to start.

https://dba.stackexchange.com/questions/237359/aws-rds-postgresql-master-user-lost-all-privileges-after-upgrading-from-v9-6

When ugprading to Postgres 10 on AWS RDS, Confluence can't find start, will errors 'bandana table does not exist'.
It's because after upgrade, public schema lost access privileges.

Steps to Reproduce

1. Connect to postgres sever (psql)
2. connect to confluence database by \c confluence
3. list out schemas \dn+

Expected Results

1. rdsadmin user has access privileges

                          List of schemas
  Name  |  Owner   |  Access privileges   |      Description
--------+----------+----------------------+------------------------
 public | rdsadmin | rdsadmin=UC/rdsadmin+| standard public schema
        |          | =UC/rdsadmin         |
(1 row)

Actual Results

1. access privileges are lost.

       List of schemas
     Name  |  Owner   | Access privileges |      Description
   --------+----------+-------------------+------------------------
    public | rdsadmin |                   | standard public schema
   (1 row)
   

Workaround

Grant schema access to confluence user.

confluence=> ALTER SCHEMA public OWNER to atlconfluence;
ALTER SCHEMA
confluence=> GRANT ALL ON SCHEMA public TO atlconfluence;
GRANT