Reload the content of the bufnr buffer

import type { Denops } from "https://deno.land/x/denops_std@v6.0.0/mod.ts";
import * as fn from "https://deno.land/x/denops_std@v6.0.0/function/mod.ts";
import { open, reload } from "https://deno.land/x/denops_std@v6.0.0/buffer/mod.ts";

export async function main(denops: Denops): Promise<void> {
  await open(denops, "README.md");
  const bufnr = await fn.bufnr(denops);
  // ...
  // Reload the content of the `bufnr` buffer.
  await reload(denops, bufnr);
}

It may temporary change a current buffer or a current window to properly reload the content of the bufnr buffer.