[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 7a6d6f0 [InstCombine] improve folds for icmp with multiply operands (PR47432)
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   7a6d6f0..5ea9e65  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 5ea9e655efdd1188d9864a6c97a7a9b772559ff5.
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!