bpo-34011: Fixes missing venv files and other tests (GH-9458)

diff --git a/Tools/msi/distutils.command.bdist_wininst.py b/Tools/msi/distutils.command.bdist_wininst.py
index d586e34..548fdd0 100644
--- a/Tools/msi/distutils.command.bdist_wininst.py
+++ b/Tools/msi/distutils.command.bdist_wininst.py
@@ -9,6 +9,9 @@
 class bdist_wininst(Command):
     description = "create an executable installer for MS Windows"
 
+    # Marker for tests that we have the unsupported bdist_wininst
+    _unsupported = True
+
     def initialize_options(self):
         pass