[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 89b7220 [LLDB][TestSuite] Improve skipIfWindowsAndNonEnglish in decorators.py
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   89b7220..ae3625d  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to ae3625d7526f50c39784ca6b0532a74c059516c2.
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!