use server-side to ensure null fields are not overwritten (#643)

Author: adwk67

docs/modules/druid/examples/getting_started/getting_started.sh

@@ -114,7 +114,7 @@ kubectl rollout status --watch statefulset/simple-hdfs-namenode-default --timeou
 
 echo "Install DruidCluster from druid.yaml"
 # tag::install-druid[]
-kubectl apply -f druid.yaml
+kubectl apply --server-side -f druid.yaml
 # end::install-druid[]
 
 for (( i=1; i<=15; i++ ))

docs/modules/druid/examples/getting_started/getting_started.sh.j2

@@ -114,7 +114,7 @@ kubectl rollout status --watch statefulset/simple-hdfs-namenode-default --timeou
 
 echo "Install DruidCluster from druid.yaml"
 # tag::install-druid[]
-kubectl apply -f druid.yaml
+kubectl apply --server-side -f druid.yaml
 # end::install-druid[]
 
 for (( i=1; i<=15; i++ ))