[DCAEGEN2][bootstrap] Use common secret template for postgres credentials

Even through we use common secret template both passwords are still
hardcoded in common postgres chart but this will be removed as a final
step just like we did for mariadb-galera.

Issue-ID: OOM-2250
Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Change-Id: Icaa5334d6ebad4fbce23ed4f59b74448c02783cf
diff --git a/kubernetes/dcaegen2/components/dcae-bootstrap/resources/inputs/k8s-pgaas-initdb-inputs.yaml b/kubernetes/dcaegen2/components/dcae-bootstrap/resources/inputs/k8s-pgaas-initdb-inputs.yaml
index 23bb080..eb4cf25 100644
--- a/kubernetes/dcaegen2/components/dcae-bootstrap/resources/inputs/k8s-pgaas-initdb-inputs.yaml
+++ b/kubernetes/dcaegen2/components/dcae-bootstrap/resources/inputs/k8s-pgaas-initdb-inputs.yaml
@@ -16,4 +16,4 @@
 # ============LICENSE_END=========================================================
 
 k8s_pgaas_instance_fqdn: {{ .Values.postgres.service.name2 }}.{{include "common.namespace" . }}
-k8s_initial_password: {{ .Values.postgres.config.pgRootPassword }}
+k8s_initial_password: $PG_ROOT_PASSWORD