version: Update ITK to v5.1.0

Author: thewtex

CMakeLists.txt

@@ -73,8 +73,8 @@ if(ITKPythonPackage_SUPERBUILD)
   include(ExternalProject)
 
   set(ITK_REPOSITORY "https://github.com/InsightSoftwareConsortium/ITK.git")
-  # ITK release 2020-04-23
-  set(ITK_GIT_TAG "1db195961d029cfc0143de20f4430c20a53ea577")
+  # ITK release 2020-04-25
+  set(ITK_GIT_TAG "v5.1.0")
 
   #-----------------------------------------------------------------------------
   # A separate project is used to download ITK, so that it can reused