Add "flush=True" to progress-bar print statements

Due to terminal I/O buffering, the dots came out in batches when without the "flush=True" argument. This was confusing, and defeats the purpose of the dots being a progress bar for inexperienced users.

Author: HinTak

site/en/tutorials/generative/style_transfer.ipynb

@@ -902,7 +902,7 @@
         "  for m in range(steps_per_epoch):\n",
         "    step += 1\n",
         "    train_step(image)\n",
-        "    print(\".\", end='')\n",
+        "    print(\".\", end='', flush=True)\n",
         "  display.clear_output(wait=True)\n",
         "  display.display(tensor_to_image(image))\n",
         "  print(\"Train step: {}\".format(step))\n",
@@ -1171,7 +1171,7 @@
         "  for m in range(steps_per_epoch):\n",
         "    step += 1\n",
         "    train_step(image)\n",
-        "    print(\".\", end='')\n",
+        "    print(\".\", end='', flush=True)\n",
         "  display.clear_output(wait=True)\n",
         "  display.display(tensor_to_image(image))\n",
         "  print(\"Train step: {}\".format(step))\n",