Fix failing tests

[fdiblen]

The test workflow is failing because of changes in the dependencies. We need to fix that.

Log of pytest step:

=================================== FAILURES ===================================
_______________________________ test_prospector ________________________________

baked_with_development_dependencies = local('/tmp/pytest-of-runner/pytest-0/test_prospector0/cookies/bake00/my-python-project')
project_env_bin_dir = '/tmp/pytest-of-runner/pytest-0/test_prospector0/env/bin/'

    def test_prospector(baked_with_development_dependencies, project_env_bin_dir):
        project_dir = baked_with_development_dependencies
        bin_dir = project_env_bin_dir

        result = run([f'{bin_dir}prospector'], project_dir)
>       assert result.returncode == 0
E       assert 1 == 0
E         -1
E         +0

tests/test_project.py:150: AssertionError
---------------------------- Captured stdout setup -----------------------------

also

----------------------------- Captured stdout call -----------------------------
Messages
========

.prospector.yml
  Line: 18
    profile-validator: deprecated-tool-code / pep8 tool has been renamed to 'pycodestyle'. Using pep8 to configure the tool will be removed in prospector 2.0+.
  Line: 21
    profile-validator: deprecated-tool-code / pep257 tool has been renamed to 'pydocstyle'. The name pep257 will be removed in prospector 2.0+.

See https://github.com/NLeSC/python-template/runs/5477252582?check_suite_focus=true