Fix typos in rel_ext_01_task.ipynb

Fix two small typos

rel_ext_01_task.ipynb

@@ -1412,7 +1412,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Not surprisingly, the performance of even this extremely simplistic model is noticeably better than random guessing. Of course, recall is much worse across the board, but precision and F<sub>0.5</sub>-score are sometimes much better. We observe big gains especially on `adjoins`, `author`, `contains`, `founders`, `has_sibling`, and `has spouse`. Then again, at least one relation actually got worse. (Can you offer any explanation for that?)\n",
+    "Not surprisingly, the performance of even this extremely simplistic model is noticeably better than random guessing. Of course, recall is much worse across the board, but precision and F<sub>0.5</sub>-score are sometimes much better. We observe big gains especially on `adjoins`, `author`, `has_sibling`, and `has_spouse`. Then again, at least one relation actually got worse. (Can you offer any explanation for that?)\n",
     "\n",
     "Admittedly, performance is still not great in absolute terms. However, we should have modest expectations for performance on this task — we are unlikely ever to get anywhere near perfect precision with perfect recall. Why?\n",
     "\n",