removed irrelevant note

ml_for_neuro/chapters/chapter_01/exercise_01.ipynb

@@ -19,7 +19,6 @@
     "\n",
     "* The dataset is shared as [a GitHub repository](https://github.com/mdcollab/covidclinicaldata) containing a directory of CSV files.\n",
     "* It is collected by two US-based companies providing services in the health industry.\n",
-    "* The number of observations is still relatively small, but more are added weekly and the quality of the data is high (there are many features to work with and it is relatively organized and \"clean\").\n",
     "* There are also chest X-rays available for some of the patients, that were not included in this analysis.\n",
     "\n",
     "So far so good, let's get to work. "