Bump urllib3 from 1.25.2 to 1.25.3

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.25.2 to 1.25.3.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/master/CHANGES.rst)
- [Commits](urllib3/urllib3@1.25.2...1.25.3)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot-support

requirements.txt

@@ -3,4 +3,4 @@ chardet==3.0.4
 idna==2.8
 requests==2.22.0
 Unidecode==1.0.23
-urllib3==1.25.2
+urllib3==1.25.3