retry-handler should pass any error to retry method

if we pass AbortSignal with timeout, to limit the request time, in case of a timeout, the controller will be aborted in this case, retry handler assumes there is no reason to retry the request.

I want to move the decision to the user, the user may decide to mutate the "opts", pass new AbortSignal, and retry the request.

The implementation should look like...

Need to change

if (controller?.aborted || isDisturbed(this.opts.body)) {
  this.handler.onResponseError?.(controller, err)
  return
}

to

if (isDisturbed(this.opts.body)) {
  this.handler.onResponseError?.(controller, err)
  return
}

then use can do

new RetryAgent(new Agent(), {
  retry: (err, { state, opts }, cb) => {
    if (err.code === DOMException.TIMEOUT_ERR)
       opts.signal = AbortSignal.timeout(...)
       cb()
       return
    }
    
    cb(err)
  }
})

Start by locating the retry-handler condition that checks controller?.aborted and isDisturbed(this.opts.body), then read how RetryAgent invokes the retry callback. Done means errors from an aborted controller reach the user retry method unless the request body is disturbed, allowing the callback to replace opts.signal and retry.