Help with testing of PR 12705 (macOS 10.13 High Sierra)

[Vadim-Valdis Yudaev]

Help check if lua-language-server builds successfully for macOS 10.13.

In terms of what's needed:
* Update the Portfile for lua-language-server, per the PR on macOS 10.13
* Runt `sudo port build lua-language-server`
* Wait for the build

PR: https://github.com/macports/macports-ports/pull/12705
Portfile: https://github.com/macports/macports-ports/blob/56a4d1caee70a6650359992a6a6f30c17d6176ea/lua/lua-language-server/Portfile

- Vadim-Valdis Yudaev