postgresql: Remove myself from maintainers (helm#7341)

* postgresql: Remove myself from maintainers

I have not been responsive to requests in the past year. In order avoid frustrations  with future PRs I withdraw myself from the list.

* bump chart version

Signed-off-by: jenkin-x <jicowan@hotmail.com>

stable/postgresql/Chart.yaml

@@ -1,5 +1,5 @@
 name: postgresql
-version: 0.15.0
+version: 0.15.1
 appVersion: 9.6.2
 description: Object-relational database management system (ORDBMS) with an emphasis on extensibility and on standards-compliance.
 keywords:
@@ -12,6 +12,5 @@ icon: https://www.postgresql.org/media/img/about/press/elephant.png
 sources:
 - https://github.com/kubernetes/charts
 - https://github.com/docker-library/postgres
-maintainers:
-- name: databus23
+maintainers: []
 engine: gotpl