test: VolumeSuite.TestVolumeTransmitAPI failing to delete volume

[josephglanville]

Relevant excerpt:

test_volume.go:18:
    s.doVolumeTransmitAPI(hosts[0], hosts[0], t)
test_volume.go:63:
    t.Assert(h1.DestroyVolume(vol2.ID), c.IsNil)
... value httphelper.JSONError = httphelper.JSONError{Code:"unknown_error", Message:"Something went wrong", Detail:json.RawMessage(nil), Retry:false} ("unknown_error: Something went wrong")

Full log: https://ci.flynn.io/builds/20160704171721-ced95389

[titanous]

The error from the host is:

cannot destroy 'flynn-default/e6886cba-cde8-4b69-be56-8a28120ece0e': dataset is busy

[titanous]

Let's wait for #3030 before looking into this further, it could be related to the mount leaks we've seen with libvirt-lxc.

[titanous]

I believe this was fixed by #3030.