[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at f9fec04 [llvm] Make ZLIB handling compatible with multi-configuration generators
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   f9fec04..f250eb3  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to f250eb37cd4fabcc9f222ca2da80b62d110d9fff.
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!