Install TensorBoard for doc generation (#19810)
Summary:
In order to have `torch.utils.tensorboard.SummaryWriter` rendered in the documentation at the bottom of https://pytorch.org/docs/master/tensorboard.html we need to have TensorBoard installed.
This change makes it so our pinned version of `tb-nightly` is used for doc generation same as it is used for running tests at https://github.com/pytorch/pytorch/blob/master/.jenkins/pytorch/test.sh#L45-L52
Eventually we'll use a pinned version of `pip install tensorboard`, but it's not on the release channel yet.
cc kostmo soumith ezyang
Pull Request resolved: https://github.com/pytorch/pytorch/pull/19810
Differential Revision: D15101730
Pulled By: orionr
fbshipit-source-id: c41678c4f9ef3d56a168f2b96a1ab05f351bdc56
