Bump urllib3 from 1.24.1 to 1.26.5

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.24.1 to 1.26.5.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](https://github.com/urllib3/urllib3/compare/1.24.1...1.26.5)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-type: direct:production
...

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

requirements.txt

@@ -46,6 +46,6 @@ termcolor==1.1.0
 toolz==0.9.0
 torch==0.4.1
 torchvision==0.2.1
-urllib3==1.24.1
+urllib3==1.26.5
 Werkzeug==0.14.1
 youtube-dl==2018.11.7