[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at b2c0193 [DSE] Add tests with lifetime.end that only mark parts of the obj as dead.
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   b2c0193..a61272a  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to a61272a900296573902dfce99274fd335239a4d3.
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!