Bump urllib3 from 1.24.1 to 1.24.2

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.24.1 to 1.24.2.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/master/CHANGES.rst)
- [Commits](urllib3/urllib3@1.24.1...1.24.2)

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -33,6 +33,6 @@ tox==3.6.1
 tqdm==4.29.0
 twine==1.12.1
 typing==3.6.6
-urllib3==1.24.1
+urllib3==1.24.2
 virtualenv==16.2.0
 webencodings==0.5.1