FIX handling json data with multibyte characters
FIX handling json data with multibyte characters

"json.dumps" function returns encoded value when specifying
"ensure_ascii=False", so it's not necessary to encode the returned
value.

Change-Id: Ic4834a27d36993cd9f4d2b6945cf108e7149d95b
Closes-Bug: 1569112

stackforge/monasca-common,stackforge/monasca-common,openstack/monasca-common,openstack/monasca-common,openstack/monasca-common,stackforge/monasca-common