devel/lua-lunitx: New port

Lunitx is a unit testing framework for lua, written in lua,
based heavily on Lunit 0.5, but modified to work with Lua 5.2.
Lunitx provides 27 assert functions, and a few misc functions
for usage in an easy unit testing framework.
Lunit comes with a test suite to test itself. The testsuite
consists of approximately 710 assertions.

The port is required test of lua-sqlite3.

PR: 286201