Bump postgresql chart (used for testing only)

Author: manics

.github/workflows/test-chart.yaml

@@ -203,7 +203,7 @@ jobs:
             create-k8s-test-resources: true
             # https://artifacthub.io/packages/helm/bitnami/postgresql
             setup-postgresql-args: >-
-              --version=11.6.13
+              --version=16.0.5
               --set auth.enablePostgresUser=true
               --set auth.postgresPassword=postgres
               --set auth.database=jupyterhub