GitHub Vulnerability Alert: urllib3 version 1.22

[corpetty]

Github has sent us a vulnerability alert of one of our dependencies: urllib3 version 1.22, which has been labeled High Severity.

You can find more information here.

Suggested fix from Github:

upgrade to urllib3>=1.23 in test/end-to-end/requirements.txt.

Notes: there seems to be breaking changes going to 1.23, and the current version is 1.24, so a few tests to make sure nothing is broken with how we use it will be necessary.