graph service: add tests for the python client
$ ./setup.py test
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Ran 0 tests in 0.000s
OKMigrated from T1920 (view on Phabricator)
Staging instance, all changes can be removed at any time
$ ./setup.py test
----------------------------------------------------------------------
Ran 0 tests in 0.000s
OKMigrated from T1920 (view on Phabricator)