[spark-operator] Fix port conflict in GKE (#1132)

Author: gtopper

stable/spark-operator/Chart.yaml

@@ -1,7 +1,7 @@
 apiVersion: v2
 name: spark-operator
 description: A Helm chart for Spark on Kubernetes operator.
-version: 2.0.20
+version: 2.0.21
 appVersion: 2.2.1
 keywords:
 - apache spark

stable/spark-operator/values.yaml

@@ -411,8 +411,9 @@ prometheus:
   metrics:
     # -- Specifies whether to enable prometheus metrics scraping.
     enable: true
-    # -- Metrics port.
-    port: 8080
+    # -- Metrics port. Use a high port to avoid collisions
+    # -- e.g. GKE reserves 8080 for node-local-dns when hostNetwork is used (IG-25049)
+    port: 28282
     # -- Metrics port name.
     portName: metrics
     # -- Metrics serving endpoint.