[BUG] ESR failure plot doesn't show.

[sdatkinson]

There's a plot that's supposed to show, but it doesn't.

e.g. On Colab (lower white space is Tensorboard, not the desired plot):

Observed on local as well.

Solve by gathering all plot events and doing plt.show() at once. (Though this probably won't work if one tries to train twice in the same local session; Colab should be fine. Matplotlib is just annoying in general about this. Sigh.)