Bump urllib3 from 2.5.0 to 2.6.0 in /images/singleuser-sample

Bumps [urllib3](https://github.com/urllib3/urllib3) from 2.5.0 to 2.6.0.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](urllib3/urllib3@2.5.0...2.6.0)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-version: 2.6.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

images/singleuser-sample/requirements.txt

@@ -323,7 +323,7 @@ tzdata==2025.2
     # via arrow
 uri-template==1.3.0
     # via jsonschema
-urllib3==2.5.0
+urllib3==2.6.0
     # via requests
 wcwidth==0.2.14
     # via prompt-toolkit