Boolean pixel values are no longer supported in VTK 9.2.

diff --git a/addons/vtk/test_vtkimage.cc b/addons/vtk/test_vtkimage.cc
--- a/addons/vtk/test_vtkimage.cc
+++ b/addons/vtk/test_vtkimage.cc
@@ -206,7 +206,7 @@ BOOST_AUTO_TEST_CASE_TEMPLATE( test_mhd_write_read, T, type_mhd )
        unlink(zrawfilename.str().c_str());
 }
 
-#if  VTK_MAJOR_VERSION >= 7
+#if  VTK_MAJOR_VERSION >= 7 && VTK_MAJOR_VERSION < 9
 BOOST_AUTO_TEST_CASE( test_simple_write_read_bool )
 {
        C3DBounds size(2, 3, 4);