Refactor project to use Poetry and add PR Gate

[vs4vijay]

This pull request introduces several significant changes to the ScanMaster project, focusing on dependency management, continuous integration, and code organization.

• Dependency Management: Migrates the project from using pip and a requirements.txt file for managing dependencies to using Poetry. This is achieved by deleting the requirements.txt and setup.sh files and adding a pyproject.toml file to define project dependencies and configurations. The README.md file is updated to reflect these changes, instructing users to use Poetry for installation.
• Continuous Integration: Establishes a PR Gate using GitHub Actions. A new workflow file .github/workflows/pr_gate.yml is added, defining steps for linting and testing the codebase on pull requests.
• Code Organization: Refactors the scanner implementations to improve code reuse and maintenance. Changes in scanners/__init__.py and modifications to scanners/openvas_scanner.py are part of this effort, aiming to centralize and streamline the way scanner modules are imported and utilized within the project.

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud