[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at e0e7eb2 [clang] Add missing .def files to Clang's modulemap
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   e0e7eb2..0e86f39  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 0e86f390457a2b4dd1f2d1770db912963a36f240.
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!