Updates hard requirements on pyproject.tomls

[staticdev]

To change this behavior and generate a new poetry.lock, I had to temporarily remove example_isort_formatting_plugin as dev-dependency, since it depends on isort.

• After we have a new version of isort, we can add this new version on example_isort_formatting_plugin and then generate a new version of it.
• Then by readding the dev dependency, everything will have uncapped python_requires 4.0.

Closes #1877