Utilities/Release: Do not upload doc staging tarball

Restrict the release upload globbing pattern to match the CMake version
so that "cmake-<v>*" files go but "cmake-<id>-docs.tar.gz" does not.

Utilities/Release/upload_release.cmake

@@ -1,10 +1,10 @@
 set(CTEST_RUN_CURRENT_SCRIPT 0)
-if(NOT DEFINED PROJECT_PREFIX)
-  set(PROJECT_PREFIX cmake-)
-endif()
 if(NOT VERSION)
  set(VERSION 3.0)
 endif()
+if(NOT DEFINED PROJECT_PREFIX)
+  set(PROJECT_PREFIX cmake-${VERSION})
+endif()
 set(dir "v${VERSION}")
 if("${VERSION}" MATCHES "master")
   set(dir "dev")