tests: don't install a setuptools newer than 81.x

Some of the ancient package versions we are testing are depending on
pkg_resources that got dropped in setuptools 82.

Author: xrmx

tests/scripts/run_tests.sh

@@ -3,7 +3,8 @@
 set -e
 
 export PATH=${HOME}/.local/bin:${PATH}
-python -m pip install --user -U pip setuptools --cache-dir "${PIP_CACHE}"
+# setuptools 82 dropped pkg_resources but that is required by some old versions of packages we are testing
+python -m pip install --user -U pip 'setuptools<82' --cache-dir "${PIP_CACHE}"
 python -m pip install --user -r "tests/requirements/reqs-${FRAMEWORK}.txt" --cache-dir "${PIP_CACHE}"
 
 export PYTHON_VERSION=$(python -c "import platform; pv=platform.python_version_tuple(); print('pypy' + ('' if pv[0] == 2 else str(pv[0])) if platform.python_implementation() == 'PyPy' else '.'.join(map(str, platform.python_version_tuple()[:2])))")