[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 1e392fc [ArgPromotion] Replace all md uses of promoted values with undef.
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   1e392fc..3e89cbf  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 3e89cbf38e76d0d0ac75fe77d318a5cfeac512f5.
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!