Utilities/Release: Update README to reference https URL

Utilities/Release/README

@@ -1,7 +1,7 @@
 To create a cmake release, make sure the "release" tag is pointing to the
 expected git commit:
 
-http://cmake.org/gitweb?p=cmake.git;a=shortlog;h=refs/heads/release
+https://cmake.org/gitweb?p=cmake.git;a=shortlog;h=refs/heads/release
 
 Then as kitware@hythloth, using an up-to-date CMake: