[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at bbb5dc4 [mlir][openacc] Add acc.data operation verifier
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   bbb5dc4..b9f2b3b  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to b9f2b3bc431a0053159939a4132814fb113af131.
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!