disable windows tbb build first

setup.py

@@ -52,7 +52,6 @@ def build_extension(self, ext: CMakeExtension) -> None:
             f"-DCMAKE_LIBRARY_OUTPUT_DIRECTORY={extdir}{os.sep}",
             f"-DPYTHON_EXECUTABLE={sys.executable}",
             f"-DCMAKE_BUILD_TYPE={cfg}",  # not used on MSVC, but no harm
-            "-DMANIFOLD_PAR=TBB",
             "-DBUILD_SHARED_LIBS=ON"
         ]
         build_args = []
@@ -67,6 +66,7 @@ def build_extension(self, ext: CMakeExtension) -> None:
             f"-DEXAMPLE_VERSION_INFO={self.distribution.get_version()}"]
 
         if self.compiler.compiler_type != "msvc":
+            cmake_args += [ "-DMANIFOLD_PAR=TBB" ]
             # Using Ninja-build since it a) is available as a wheel and b)
             # multithreads automatically. MSVC would require all variables be
             # exported for Ninja to pick it up, which is a little tricky to do.