RHDHBUGS-2557: Rename deprecated janus-idp Helm template references to rhdh

Replace 3 deprecated janus-idp.* Helm named template references with
their rhdh.* counterparts, matching the rename done in the Helm chart
repo (RHDHBUGS-2159).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: themr0c

modules/configure_configuring-rhdh/proc-configure-an-external-postgresql-instance-using-the-helm-chart.adoc

@@ -122,7 +122,7 @@ upstream:
       valueFrom:
         secretKeyRef:
           key: backend-secret
-          name: '{{ include "janus-idp.backend-secret-name" $ }}'
+          name: '{{ include "rhdh.backend-secret-name" $ }}'
   extraVolumeMounts:
     - mountPath: /opt/app-root/src/dynamic-plugins-root
       name: dynamic-plugins-root

modules/configure_configuring-rhdh/proc-fix-helm-overwriting-predefined-arrays.adoc

@@ -25,12 +25,12 @@ extraEnvVars:
         valueFrom:
           secretKeyRef:
             key: backend-secret
-            name: '{{ include "janus-idp.backend-secret-name" $ }}'
+            name: '{{ include "rhdh.backend-secret-name" $ }}'
       - name: POSTGRESQL_ADMIN_PASSWORD
         valueFrom:
           secretKeyRef:
             key: postgres-password
-            name: '{{- include "janus-idp.postgresql.secretName" . }}'
+            name: '{{- include "rhdh.postgresql.secretName" . }}'
 ----
 
 . For `extraVolumeMounts`, add the following content to your `values.yaml` file: