[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at bd2fa18 [OpenMPOpt][HideMemTransfersLatency] Moving the 'wait' counterpart of __tgt_target_data_begin_mapper
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   bd2fa18..8e4acb8  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 8e4acb82f71ad4effec8895b8fc957189ce95933.
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!