[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 1bb68c9 [sanitizer] Allow log_path to distinguish default from explicit stderr
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   1bb68c9..e285899  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to e2858997abcb0e0960849b4eed5bf894889d2329.
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!