[Development] Upgrade the XCode running in the CI's macOS 10.11

[Thiago Macieira]

On Monday, 9 July 2018 07:31:27 PDT Alexandru Croitor wrote:
> I believe that's something for the macOS maintainers to decide.

Thanks. Any opinions?

The fix for XCode 8.2 broke XCode 9.

Can we PLEASE drop XCode 8.2? Like, right now? I can't integrate the 
performance improvement until that happens.

-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center