Update the default versions to 6.1.0 (CMB) and 3.1.0(SMTK)

versions.cmake

@@ -18,9 +18,9 @@ superbuild_set_revision(vtkonly
   GIT_TAG        "v8.2.0")
 
 superbuild_set_selectable_source(cmb
-  SELECT 6.1.0-RC1
+  SELECT 6.1.0
     GIT_REPOSITORY  "https://gitlab.kitware.com/cmb/cmb.git"
-    GIT_TAG         "v6.1.0-rc2"
+    GIT_TAG         "v6.1.0"
   SELECT git CUSTOMIZABLE DEFAULT
     GIT_REPOSITORY  "https://gitlab.kitware.com/cmb/cmb.git"
     GIT_TAG         "origin/release"
@@ -28,9 +28,9 @@ superbuild_set_selectable_source(cmb
     SOURCE_DIR "source-cmb")
 
 superbuild_set_selectable_source(smtk
-  SELECT 3.1.0-RC1
+  SELECT 3.1.0
     GIT_REPOSITORY  "https://gitlab.kitware.com/cmb/smtk.git"
-    GIT_TAG         "v3.1.0-rc2"
+    GIT_TAG         "v3.1.0"
   SELECT git CUSTOMIZABLE DEFAULT
     GIT_REPOSITORY  "https://gitlab.kitware.com/cmb/smtk.git"
     GIT_TAG         "origin/release"