[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at e5dba2d [OMPIRBuilder] Start 'Create' methods with lower case. NFC.
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   e5dba2d..1cbf8e8  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 1cbf8e89b54de939420d53d7a528bec6fbaf0a55.
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!