Add precommit job to github actions and correct linter issues

[pbadillatorrealba]

Changes:

• Pre-commit is added to the github actions so that every time a pr or merge is made to master a QA check is performed. The previous replaces the flake8 check that was done in a github action, separating it into two independent jobs: pre-commit and pytest.
• QA checks are now more comprehensive with pre-commit: errors with flake and styles with black and isort.
• Many style and type changes are made to the code to to correct the problems shown by precommit.
• In addition, a new linter was experimentally tested with more demanding rule sets than precommit: ruff. It was configured in pyproject.toml and the errors associated with the selected rules were corrected.