Updating en/computer-vision-deep-learning to reflect transition from Kaggle to Google Colab

[charlottejmc]

The lesson en/computer-vision-deep-learning (-pt1 and -pt2) was originally accompanied by a Jupyter notebook, which was hosted on the authors' personal Kaggle account. This was a problem for us, as we did not have access to it for maintenance, and therefore could not ensure sustainability into the future.

Since the publication of this lesson, we've developed some guidelines on the use of notebooks within lessons, and decided that we would only host notebooks through our own Google account, therefore using Google Colab over any other cloud-based option.

The lesson's authors have very kindly reached out with a copy of their original notebook now on Colab, which has just been uploaded to /assets/computer-vision-deep-learning-pt-1 in commit 3f72563.

We now need to update the text within the lesson (both parts) to reflect this change.

I will prepare a first draft of these updates, and involve the managing editor and the lesson's original authors by asking them to review the PR and ensure they are happy with the changes.