[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 4fc69ab Revert "[OpenMP][FIX] Verify compatible types for declare variant calls"
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   4fc69ab..98ef7e2  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 98ef7e29b0fe03da77fa6ef5c86bea9e31c178d0.
CMake Error at CMakeLists.txt:3 (cmake_minimum_required):
  CMake 3.13.4 or higher is required.  You are running version 3.7.1


-- Configuring incomplete, errors occurred!