[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 3f7985e [AMDGPU][MC][NFC][DOC] Updated AMD GPU assembler syntax description.
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   3f7985e..bfc6d8b  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to bfc6d8b59b7b3f736f43ba16666c1f7ed9c780e4.
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!