fix(node/fs): chmod function throws unnecessary TypeError on Windows

[PolarETech]

Fixes: #2916
Part of: denoland/deno#17841

This PR fixes an error that occurs when an invalid value is unintentionally passed to the mode parameter of the chmod and chmodSync functions on Windows.
This change will make npm:fs-extra.copy() work on Windows.

NOTE: This change must be reverted if Deno.chmod and Deno.chmodSync were supported on Windows.

[kt3k]

Mostly looks good to me. Left one comment

[kt3k]

nit: How about branching by this condition before doing try block?

[PolarETech]

Then how about the following?

  path = getValidatedPath(path).toString();

  if (Deno.build.os === "windows" && mode === null) {
    mode = 0;
  }
  mode = parseFileMode(mode, "mode");

  Deno.chmod(pathModule.toNamespacedPath(path), mode).catch((error) => {

I realized that we might need to consider the case where Deno.chmod supports Windows in the future, and I assume that if Deno.chmod works, then parseFileMode must be run.
It could be the case that Deno.chmod is supported on Windows but the code here is left as is.
To prepare for such a case, I thought parseFileMode would run, and if an error occurred, setting mode to a dummy value (0 would be safest) would solve the current issue.

However, the concern remains that if a situation arises in the future where Deno.chmod supports Windows but Deno.FileInfo.mode does not, the permissions will be set to 0 unexpectedly.

[kt3k]

Thanks for the explanation. Now the current code just makes sense to me.

[kt3k]

LGTM