Problem:
- Current lua indentexpr does not indent for '(' ')'.
- Missing indent test for lua.
Solution:
- Match '(', ')' in `function GetLuaIndentIntern`.
- Add an indent test for lua.
closes: vim/vim#15364c0f7505ede
Co-authored-by: Yinzuo Jiang <jiangyinzuo@foxmail.com>