build(deps): bump contrib/nvim-plugins/lualine.nvim

Bumps [contrib/nvim-plugins/lualine.nvim](https://github.com/nvim-lualine/lualine.nvim) from `b39f1f0` to `640260d`.
- [Commits](nvim-lualine/lualine.nvim@b39f1f0...640260d)

---
updated-dependencies:
- dependency-name: contrib/nvim-plugins/lualine.nvim
  dependency-type: direct:production
...

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