As described at [1].

----------------- Problem statement ------------------------------
The operator is failing due to the postgresql cannot start property.

Log in the postres db.
pg_ctl: another server might be running; trying to start server anyway
waiting for server to start....LOG: redirecting log output to logging collector process
HINT: Future log output will appear in directory "pg_log".
done
server started
=> sourcing /usr/share/container-scripts/postgresql/start/set_passwords.sh ...
psql: FATAL: role "postgres" does not exist
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--------- Described workaround/solution is: -------------------------------------------------

1) upgrade Che CR to use Postgres 10:
postgresImage: 'registry.access.redhat.com/rhscl/postgresql-10-rhel7:1-35'

2) delete the PVC postgres-data (since it contains data from failed 9.6 run)
-----------------------------------------------------------------------------------------------------

Please provide a permanent solution for newer versions of CRW (those that will be suitable for use with OCP 4.1)

[1] http://post-office.corp.redhat.com/archives/openshift-sme/2019-May/msg00489.html