Bump urllib3 from 1.25.9 to 1.26.5 in /sample-apps/flask (#301)

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.25.9 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@1.25.9...1.26.5)

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

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

sample-apps/flask/requirements.txt

@@ -8,7 +8,7 @@ itsdangerous==1.1.0
 Jinja2==2.11.3
 MarkupSafe==1.1.1
 requests==2.23.0
-urllib3==1.25.9
+urllib3==1.26.5
 Werkzeug==1.0.1
 flask-sqlalchemy==2.4.3
 aws_xray_sdk==2.6.0