Bump urllib3 from 1.25.8 to 1.26.4

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.25.8 to 1.26.4.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/1.26.4/CHANGES.rst)
- [Commits](urllib3/urllib3@1.25.8...1.26.4)

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

requirements.txt

@@ -5,7 +5,7 @@ jmespath==0.9.5 --hash=sha256:695cb76fa78a10663425d5b73ddc5714eb711157e52704d69b
 python-dateutil==2.8.1 --hash=sha256:75bb3f31ea686f1197762692a9ee6a7550b59fc6ca3a1f4b5d7e32fb98e2da2a
 s3transfer==0.3.3 --hash=sha256:2482b4259524933a022d59da830f51bd746db62f047d6eb213f2f8855dcb8a13
 six==1.14.0 --hash=sha256:8f3cd2e254d8f793e7f3d6d9df77b92252b52637291d0f0da013c76ea2724b6c
-urllib3==1.25.8 --hash=sha256:2f3db8b19923a873b3e5256dc9c2dedfa883e33d87c690d9c7913e1f40673cdc
+urllib3==1.26.4 --hash=sha256:2f4da4594db7e1e110a944bb1b551fdf4e6c136ad42e4234131391e21eb5b0df --hash=sha256:e7b021f7241115872f92f43c6508082facffbd1c048e3c6e2bb9c2a157e28937
 cdn-definitions==2.0.0 --hash=sha256:bb5592ab4dcac11636a523459fdbdd613460f0fdf42fb26ea6f561cbfefe600b
 requests==2.23.0 --hash=sha256:43999036bfa82904b6af1d99e4882b560e5e2c68e5c4b0aa03b655f3d7d73fee
 chardet==3.0.4 --hash=sha256:fc323ffcaeaed0e0a02bf4d117757b98aed530d9ed4531e3e15460124c106691