Cap setuptools to preserve pkg_resources

Author: domdfcoding

doc-source/requirements.txt

@@ -4,6 +4,7 @@ extras-require>=0.5.0
 html-section>=0.3.0
 roman>=4.0
 seed-intersphinx-mapping>=1.2.2
+setuptools<81
 sphinx-copybutton>=0.5.2
 sphinx-debuginfo>=0.2.2
 sphinx-licenseinfo>=0.3.1

tests/requirements.txt

@@ -7,4 +7,5 @@ pytest>=6.0.0
 pytest-cov>=2.8.1
 pytest-randomly>=3.7.0
 pytest-timeout>=1.4.2
+setuptools<81
 sphinx-toolbox[testing]>=2.13.0b3