[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 0fd0433 [LLDB] Fixing lldb/test/Shell/Register/x86-fp-write.test
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   0fd0433..91fe3e3  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 91fe3e309c7c4b2c7c906353e4b658ee704fe0bf.
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!