Run test_migrate_boot_from_vol repeatedly

gistfile1.txt

 MigrationTest
    test_migrate_boot_from_vol                                   ERROR  4.51

======================================================================
ERROR: test_migrate_boot_from_vol (teacup.tests.migration.test_migration.MigrationTest)
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Traceback (most recent call last):
  File "/home/vagrant/piston/teacup/teacup/common/skip.py", line 69, in wrapper
    return f(*args, **kw)
  File "/home/vagrant/piston/teacup/teacup/common/skip.py", line 69, in wrapper
    return f(*args, **kw)
  File "/home/vagrant/piston/teacup/teacup/tests/migration/test_migration.py", line 260, in test_migrate_boot_from_vol
    vm, key = self.boot_from_volume()
  File "/home/vagrant/piston/teacup/teacup/common/utils.py", line 600, in boot_from_volume
    vm, key = self.ensure_vm(volume=v, **kw)
  File "/home/vagrant/piston/teacup/teacup/common/utils.py", line 307, in ensure_vm
    key = self.ensure_keypair(name=keypair)
  File "/home/vagrant/piston/teacup/teacup/common/utils.py", line 220, in ensure_keypair
    key = self.nova.keypairs.create(name=name)
 File "/home/vagrant/.virtualenvs/teacup3/local/lib/python2.7/site-packages/novaclient/v1_1/keypairs.py", line 78, in create
    return self._create('/%s' % self.keypair_prefix, body, 'keypair')
  File "/home/vagrant/.virtualenvs/teacup3/local/lib/python2.7/site-packages/novaclient/base.py", line 100, in _create
    _resp, body = self.api.client.post(url, body=body)
  File "/home/vagrant/.virtualenvs/teacup3/local/lib/python2.7/site-packages/novaclient/client.py", line 490, in post
    return self._cs_request(url, 'POST', **kwargs)
  File "/home/vagrant/.virtualenvs/teacup3/local/lib/python2.7/site-packages/novaclient/client.py", line 465, in _cs_request
    resp, body = self._time_request(url, method, **kwargs)
  File "/home/vagrant/.virtualenvs/teacup3/local/lib/python2.7/site-packages/novaclient/client.py", line 439, in _time_request
    resp, body = self.request(url, method, **kwargs)
  File "/home/vagrant/.virtualenvs/teacup3/local/lib/python2.7/site-packages/novaclient/client.py", line 433, in request
    raise exceptions.from_response(resp, body, url, method)
OverLimit: Quota exceeded, too many key pairs. (HTTP 413) (Request-ID: req-2c966674-beed-4e30-9b81-500fe893656a)