TypeError: util.isDate is not a function

Hi, the error is produced in Node 23 using a package that takes `macos-alias` as a dependency.

It seems to relate to `util.isDate`
https://github.com/LinusU/node-alias/blob/fb006c2ad35af646193e8744d7b43ef95c495af6/lib/encode.js#L8
```
⠏ Making hidden background folder/opt/homebrew/lib/node_modules/create-dmg/node_modules/macos-alias/lib/encode.js:8
if (util.isDate(value) === false) {
^

TypeError: util.isDate is not a function
at appleDate (/opt/homebrew/lib/node_modules/create-dmg/node_modules/macos-alias/lib/encode.js:8:12)
at exports (/opt/homebrew/lib/node_modules/create-dmg/node_modules/macos-alias/lib/encode.js:44:23)
at Object.exports [as create] (/opt/homebrew/lib/node_modules/create-dmg/node_modules/macos-alias/lib/create.js:145:10)
at Helper.write (/opt/homebrew/lib/node_modules/create-dmg/node_modules/ds-store/index.js:50:22)
at Object.fn (/opt/homebrew/lib/node_modules/create-dmg/node_modules/appdmg/lib/appdmg.js:391:8)
at Pipeline._runStep (/opt/homebrew/lib/node_modules/create-dmg/node_modules/appdmg/lib/pipeline.js:46:10)
at Pipeline._run (/opt/homebrew/lib/node_modules/create-dmg/node_modules/appdmg/lib/pipeline.js:94:10)
at next (/opt/homebrew/lib/node_modules/create-dmg/node_modules/appdmg/lib/pipeline.js:35:25)
at /opt/homebrew/lib/node_modules/create-dmg/node_modules/async/lib/async.js:52:16
at done (/opt/homebrew/lib/node_modules/create-dmg/node_modules/async/lib/async.js:246:17)

Node.js v23.1.0
```
https://github.com/sindresorhus/create-dmg/issues/93

Start at lib/encode.js:8 and reproduce the failure with Node.js 23.1.0, using the existing stack trace to follow how appleDate is called. Confirm the date-handling behavior and verify that alias creation works on the reported Node version without breaking supported behavior.

Written by the indexing model from the issue text.