implement OSPO guidelines

[sbasan]

Pull Request summary:

Fix issues after OSPO review

Description of changes:

1. Include copyright notice in each python source file
2. Add code guidelines section link in CONTRIBUTING.md
3. Fix catalystwan/models/configuration/feature_profile/README.md
4. Fix catalystwan/api/templates/README.md
5. Apply inclusive language policy when possible.
   • bumped version and regenerated ENDPOINTS.md to include renamed items
   • some strings cannot be removed as they're defined externally eg.:
     GET /template/policy/list/urlwhitelist
https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information

Checklist:

• Make sure to run pre-commit before committing changes
• Make sure all checks have passed
• PR description is clear and comprehensive
• Mentioned the issue that this PR solves (if applicable)
• Make sure you test the changes