[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at ca2e7e5 [IRGen] Add !annotation metadata for auto-init stores.
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   ca2e7e5..0bee8c7  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 0bee8c784b3f9303cb77336b18f65d45439e066a.
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!