Bump urllib3 from 1.23 to 1.26.5

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.23 to 1.26.5.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](urllib3/urllib3@1.23...1.26.5)

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

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

Author: dependabot[bot]

requirements.txt

@@ -35,6 +35,6 @@ toga-cocoa==0.3.0.dev13
 toga-core==0.3.0.dev13
 travertino==0.1.2
 twilio==6.29.3
-urllib3==1.23
+urllib3==1.26.5
 voc==0.1.6
 whichcraft==0.6.0

setup.py

@@ -51,7 +51,7 @@
         'six==1.12.0',
         'SQLAlchemy==1.3.6',
         'twilio==6.29.3',
-        'urllib3==1.24.3',
+        'urllib3==1.26.5',
 	'numpy==1.17.1',
 	'setuptools==41.2.0',
         ],