ENH: Increase coverage for miscellaneous classes

Increase coverage for miscellaneous classes:
- Exercise basic object methods using the
  `ITK_EXERCISE_BASIC_OBJECT_METHODS` macro. Remove redundant calls to
  print the filter: rely on the basic method exercising macro call.

Modules/Numerics/Statistics/test/itkKdTreeGeneratorTest.cxx

@@ -18,6 +18,7 @@
 
 #include "itkListSample.h"
 #include "itkKdTreeGenerator.h"
+#include "itkTestingMacros.h"
 
 int
 itkKdTreeGeneratorTest(int, char *[])
@@ -44,7 +45,8 @@ itkKdTreeGeneratorTest(int, char *[])
     using TreeGeneratorType = itk::Statistics::KdTreeGenerator<SampleType>;
     auto treeGenerator = TreeGeneratorType::New();
 
-    std::cout << "KdTreeGenerator class name: " << treeGenerator->GetNameOfClass() << std::endl;
+    ITK_EXERCISE_BASIC_OBJECT_METHODS(treeGenerator, KdTreeGenerator, Object);
+
 
     treeGenerator->SetSample(sample);
     treeGenerator->SetBucketSize(16);

Modules/Numerics/Statistics/test/itkKdTreeTest1.cxx

@@ -67,6 +67,7 @@ itkKdTreeTest1(int argc, char * argv[])
   const unsigned int bucketSize = std::stoi(argv[3]);
 
   treeGenerator->SetSample(sample);
+
   treeGenerator->SetBucketSize(bucketSize);
   treeGenerator->Update();
 

Modules/Registration/RegistrationMethodsv4/test/itkSimpleImageRegistrationTest.cxx

@@ -151,6 +151,10 @@ PerformSimpleImageRegistration(int argc, char * argv[])
 
   using AffineRegistrationType = itk::ImageRegistrationMethodv4<FixedImageType, MovingImageType>;
   auto affineSimple = AffineRegistrationType::New();
+
+  ITK_EXERCISE_BASIC_OBJECT_METHODS(affineSimple, ImageRegistrationMethodv4, ProcessObject);
+
+
   affineSimple->SetObjectName("affineSimple");
 
   // Test exceptions