`ch7/2.semantic-search.ipynb` - web server doesn't work correctly in Docker

[alexott]

IFrame shows connection refused even if web server is running.

But in general - it's not clear why we need it in this notebook...

[alexott]

Ok, the "connection refused" happens because it's trying to call localhost, and I did run it on a remote host. Changing from localhost to the actual IP fixed the issue - we need to add a comment about it.

[treygrainger]

It's just running in the notebook to be consistent with the rest of the book (since everything runs in notebooks). Thanks for re-reviewing.

[alexott]

Fixed in the latest versions