ci: update virtualenv to higher than 20.26.6

[krishnanand5]

Description

This PR aims to address a CVE-2024-53899 vulnerability detected on py_maidr.

Type of Change

• Bug fix
• New feature
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Vulnerability patch

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

Pull Request

Description

The Github autoscan of the py_maidr repository identified a CVE-2024-53899 vulnerability with the repository. Upon further investigation, it was revealed that the issue is with virtualenv before 20.26.6 as it allows command injection through the activation scripts for a virtual environment.

Related Issues

GHSA-rqc4-2hc7-8c8v - Github Advisory's account of CVE-2024-53899.

Changes Made

Virtualenv has been bumped up to 20.28.1.