change current code style to be valid with black, isort and flake8

[FelixTheC]

• create a pyprojects.toml
• add necessary settings for black, isort and flake8 (see below)
• run all linters to change the style initialy before merging Add test ci #38

[tool.black]
line-length = 100
target-version = ['py39']

[tool.isort]
combine_as_imports = true
line_length = 100
profile = "black"