Add json to mock modules list
Add json to mock modules list

In order to retain sanity when dealing with json data in the hassio
test, the test uses the json library to manipulate a dict for the test.
As such, json needs to be include MOCK_MODULES.

Signed-off-by: David Wahlstrom <a6fdcaedb03335d9b13c62849f130b1043344ac9@gmail.com>

drwahl/i3pystatus,drwahl/i3pystatus