Fix one usage of `get_ident`
Fix one usage of `get_ident`

This gets rid of the corresponding DeprecationWarning when using
DjangoClient.capture:

/Users/abc/.venv/lib/python2.7/site-packages/raven/base.py:290:
DeprecationWarning: Client.get_ident is deprecated. The event ID is now returned
as the result of capture.
  DeprecationWarning)

johansteffner/raven-python,getsentry/raven-python,getsentry/raven-python,johansteffner/raven-python,getsentry/raven-python,johansteffner/raven-python