[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at e6c4d88 [clangd] NFC: Add using directives to avoid spelling out llvm::sys::path
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   e6c4d88..48e4b0f  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 48e4b0fd3a3d68cc9774699964cf4c6c2be38cf3.
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!