Compilation fails when using --output-dir=build option

[kureta]

Contents of my test file:

\documentclass{scrartcl}
\usepackage{lyluatex}

\begin{document}
\lilypond{a b c}
\end{document}

This command works: lualatex --interaction=nonstopmode --synctex=1 --shell-escape test.tex

This command fails: lualatex --interaction=nonstopmode --synctex=1 --shell-escape --output-dir=build test.tex

Error:

(lyluatex)      Compiling score tmp-ly/e2f53337204788419c76f0055ba74f56 with LilyPond executable 'lilypond'.
...re/texmf-dist/tex/lua
latex/luaoptions/luaoptions-lib.lua:236: bad argument #1 to 'rawget' (table exp
ected, got nil)
stack traceback:
        [C]: in function 'rawget'
        ...re/texmf-dist/tex/lualatex/luaoptions/luaoptions-lib.lua:236: in metamethod
 '__index'
        /usr/share/texmf-dist/scripts/lyluatex/lyluatex.lua:802: in method 'lilypond_c
md'
        /usr/share/texmf-dist/scripts/lyluatex/lyluatex.lua:1146: in method 'run_lilyp
ond'
        /usr/share/texmf-dist/scripts/lyluatex/lyluatex.lua:1110: in method 'process'
        [\directlua]:1: in main chunk.
\ly@compilescore ...directlua {ly.score:process()}

I think lyluatext is looking for necessary files right above the tmp-ly directory and fails to find any but I am not sure.

[MacLotsen]

This is a the same error described in #316. I have created a PR in luaoptions which solves this error.