[CI] Resolve dependency conflicts in GitHub Actions workflow

The GitHub Actions CI/CD workflow was failing during the pip install -r requirements.txt step due to dependency conflicts with flake8 and pylama. Specifically, mccabe==0.6.1 and pycodestyle==2.6.0 were incompatible with newer versions of these tools.

⚒️ Solution:
Updated requirements.txt to use compatible versions:

mccabe>=0.7.0

pycodestyle>=2.12.0

Ensured flake8 and pytest were explicitly listed in the requirements.txt.

Modified the GitHub Actions workflow to reflect these changes and ensure consistent installs.

✅ Outcome:
The CI pipeline now installs dependencies without conflicts and runs linting and testing as expected.