Revert "Restore Windows PowderReduceP2DTest (#39045)"

This reverts commit 1336597.

Author: ktactac-ornl

Testing/SystemTests/tests/framework/PowderReduceP2DTest.py

@@ -13,9 +13,14 @@
 class PowderReduceP2DTest(systemtesting.MantidSystemTest):
     def __init__(self):
         systemtesting.MantidSystemTest.__init__(self)
-        self.tolerance = 1.0e-6
+        self.tolerance = 1e-6
         self.setUp()
 
+    def skipTests(self):
+        # Now working on macOS but producing different outputs on windows.
+        # Skipped while investigation continues.
+        return sys.platform.startswith("win")
+
     def setUp(self):
         self.sample = self._sampleEventData()
         self.vana = self._vanadiumEventData()