Update dcos-vagrant pinned version.
Update dcos-vagrant pinned version.

mesosphere-mergebot/mergebot-test-dcos,dcos/dcos,surdy/dcos,kensipe/dcos,dcos/dcos,surdy/dcos,mesosphere-mergebot/dcos,mesosphere-mergebot/mergebot-test-dcos,mellenburg/dcos,mesosphere-mergebot/dcos,amitaekbote/dcos,dcos/dcos,amitaekbote/dcos,mesosphere-mergebot/dcos,kensipe/dcos,dcos/dcos,kensipe/dcos,mellenburg/dcos,kensipe/dcos,amitaekbote/dcos,GoelDeepak/dcos,mesosphere-mergebot/dcos,GoelDeepak/dcos,mesosphere-mergebot/mergebot-test-dcos,surdy/dcos,GoelDeepak/dcos,mesosphere-mergebot/mergebot-test-dcos,mellenburg/dcos,amitaekbote/dcos,GoelDeepak/dcos,surdy/dcos,mellenburg/dcos,dcos/dcos