Add GitHub actions to pull requests

[heyodai]

Ideas from ChatGPT:

1. Linting: Beyond formatting, linting helps catch potential errors and enforces coding standards. Tools like flake8 or pylint can be used alongside black and isort.
2. Static Analysis: Tools like mypy for type checking or bandit for finding common security issues can catch errors that are not detected by linters.
3. Code Coverage: Ensure that your tests cover a high percentage of your codebase with tools like coverage.py. This can be integrated to fail the build if the coverage falls below a certain threshold.
4. Dependency Checks: Use tools like pip-audit for Python to check for known vulnerabilities in your project dependencies.
5. Code Quality Metrics: Consider integrating a tool like SonarCloud or CodeClimate to keep track of technical debt and code complexity.
6. Documentation Checks: If you have project documentation (for example, with Sphinx), ensure it builds correctly and detect broken links.
7. Performance Benchmarking: If your project's performance is crucial, incorporate benchmarks to detect performance regressions.

Here's a sample snippet for a GitHub Action workflow including some of these suggestions:

name: Python CI

on:
  pull_request:
  push:
    branches:
      - main
    paths:
      - '**.py'

jobs:
  build:

    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v2
    - name: Set up Python
      uses: actions/setup-python@v2
      with:
        python-version: '3.8'

    - name: Install dependencies
      run: |
        pip install -r requirements.txt
        pip install black isort flake8 mypy coverage

    - name: Check code formatting with black
      run: black --check .

    - name: Sort import statements with isort
      run: isort --check-only .

    - name: Lint with flake8
      run: flake8 .

    - name: Static type-checking with mypy
      run: mypy .

    - name: Run pytest with coverage
      run: |
        coverage run -m pytest
        coverage report --fail-under=80

    - name: Check for security issues with bandit
      run: bandit -r .

[heyodai]

Another idea. Once #37 is implemented, we should add a check to verify that the version is incremented.