Allow optional 'publicServer' configuration key

Refs. swh/infra/sysadm-environment#4820

swh/templates/graphql/configmap.yaml

@@ -25,6 +25,9 @@ data:
     {{ if .Values.graphql.auth -}}
     auth:
       server: {{ .Values.graphql.auth.server | default "" }}
+      {{ if .Values.graphql.auth.publicServer -}}
+      public_server: {{ .Values.graphql.auth.publicServer }}
+      {{ end -}}
       realm: {{ .Values.graphql.auth.realm | default "" }}
       client: {{ .Values.graphql.auth.client | default "swh-web" }}
       cache:

swh/values.yaml

@@ -38,6 +38,8 @@ graphql:
   auth:
     # More information in https://gitlab.softwareheritage.org/swh/devel/swh-auth/-/blob/master/README.rst
     # server: https://auth.backend.url/
+    # optional, when not provided, graphql defaults to use "server" entry
+    # public_server: https://another.auth.backend.url/
     #realm: MyAuthDomain
     client: swh-web
     # memory:// or memcached://memcached:port