Function concat_oov_nodes 

pub fn concat_oov_nodes(
    path: Vec<ResultNode>,
    begin: usize,
    end: usize,
    pos_id: u16,
    text: &InputBuffer,
    lattice: &Lattice,
    resolver: &dyn WordInfoResolver,
) -> SudachiResult<Vec<ResultNode>>

Concatenate the nodes in the range and set pos_id.