Process() object and async operation

I am maintaining a macOS app, a GUI on top of a command line tool. A Process() object is used to kick off the command line tool with arguments. And completion handlers are triggered for post actions when command line tool is completed. My question is: I want to refactor the process to use async and await, and not use completion handlers.

func execute(command: String, arguments:[String]) -> async {

let task = Process()
task.launchPath = command
task.arguments = arguments
...
do {
    try task.run()
 } catch let e {
    let error = e
    propogateerror(error: error)
 }
...
}
...

and like this in calling the process

await execute(..)

Combine is used to monitor the ProcessTermination:

NotificationCenter.default.publisher(
            for: Process.didTerminateNotification)
            .debounce(for: .milliseconds(500), scheduler: DispatchQueue.main)
            .sink { _ in
              .....
                // Release Combine subscribers
                self.subscriptons.removeAll()
            }.store(in: &subscriptons)

Using Combine works fine by using completion handlers, but not by refactor to async. What is the best way to refactor the function? I know there is a task.waitUntilExit(), but is this 100% bulletproof? Will it always wait until external task is completed?