[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at d6aa4aa [AMDGPU] Some refactoring after D90404. NFC.
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   d6aa4aa..1267bb2  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 1267bb2e416e42f9c3bbfa7b6cbf4975fa7aa546.
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!