remove default namespace from referenced yaml file

Author: spurin

content/en/examples/application/hpa/php-apache.yaml

@@ -2,7 +2,6 @@ apiVersion: autoscaling/v1
 kind: HorizontalPodAutoscaler
 metadata:
   name: php-apache
-  namespace: default
 spec:
   scaleTargetRef:
     apiVersion: apps/v1