Merged the import for Health Appliance sample

Author: shwetapurohit

samples/vsphere/appliances/health_messages.py

@@ -17,10 +17,7 @@
 __vcenter_version__ = '6.7+'
 
 from datetime import datetime, date
-
-from samples.vsphere.common import sample_cli
-from samples.vsphere.common import sample_util
-from samples.vsphere.common import vapiconnect
+from samples.vsphere.common import (sample_cli, sample_util, vapiconnect)
 from com.vmware.appliance_client import Health
 from com.vmware.vapi.std_client import LocalizableMessage
 from com.vmware.appliance_client import Notification