[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 0381204 [NFCI] Removed an un-used declaration got accidentally introduced in f91d18eaa946b2d2ea5a9
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   0381204..722db5c  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 722db5c0b4e8dffabbd97265e5ea9edac05548ae.
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!