fixup gh selfinstall

Author: RonnyPfannschmidt

.github/workflows/python-tests.yml

@@ -96,7 +96,7 @@ jobs:
         installer: ["pip install"]
     name: check self install - Python ${{ matrix.python_version }} via ${{ matrix.installer }}
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v3
       - name: Setup python
         uses: actions/setup-python@v2
         with:
@@ -105,7 +105,7 @@ jobs:
       # self install testing needs some clarity
       # so its being executed without any other tools running
       # setuptools smaller 52 is needed to do easy_install
-      - run: pip install -U "setuptools<52" tomli packaging typing_extensions
+      - run: pip install -U "setuptools<52" tomli packaging typing_extensions importlib_metadata
       - run: python setup.py egg_info
       - run: python setup.py sdist
       - run: ${{ matrix.installer }} dist/*