[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 77d3b14 [clangd] Fix an inconsistent ReasonToReject enum usage, NFC.
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   77d3b14..fe2bd54  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to fe2bd543f5e82bc14ef37dc5ec2228812098cf7a.
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!