Move to bionic nagios image

Change-Id: I0dd1f739ea4225dc56dc5bfd1fdafd872c8e4b73
Signed-off-by: Andrii Ostapenko <andrii.ostapenko@att.com>

nagios/Chart.yaml

@@ -15,7 +15,7 @@ apiVersion: v1
 appVersion: v1.0.0
 description: OpenStack-Helm Nagios
 name: nagios
-version: 0.1.4
+version: 0.1.5
 home: https://www.nagios.org
 sources:
   - https://opendev.org/openstack/openstack-helm-addons

nagios/values.yaml

@@ -18,7 +18,7 @@
 images:
   tags:
     apache_proxy: docker.io/library/httpd:2.4
-    nagios: docker.io/openstackhelm/nagios:latest-ubuntu_xenial
+    nagios: docker.io/openstackhelm/nagios:latest-ubuntu_bionic
     dep_check: quay.io/stackanetes/kubernetes-entrypoint:v0.2.1
     selenium_tests: docker.io/openstackhelm/osh-selenium:latest-ubuntu_bionic
     image_repo_sync: docker.io/library/docker:17.07.0

releasenotes/notes/nagios.yaml

@@ -5,4 +5,5 @@ nagios:
   - 0.1.2 Use full image ref for docker official images
   - 0.1.3 Mount internal TLS CA certificate
   - 0.1.4 Update htk requirements
+  - 0.1.5 Switch nagios image from xenial to bionic
 ...