Update Azure GO SDK to v12.4.0-beta

vendor/github.com/Azure/go-autorest/autorest/sender.go

@@ -215,19 +215,26 @@ func DoRetryForStatusCodes(attempts int, backoff time.Duration, codes ...int) Se
 			rr := NewRetriableRequest(r)
 			// Increment to add the first call (attempts denotes number of retries)
 			attempts++
-			for attempt := 0; attempt < attempts; attempt++ {
+			for attempt := 0; attempt < attempts; {
 				err = rr.Prepare()
 				if err != nil {
 					return resp, err
 				}
 				resp, err = s.Do(rr.Request())
-				if err != nil || !ResponseHasStatusCode(resp, codes...) {
+				// we want to retry if err is not nil (e.g. transient network failure).  note that for failed authentication
+				// resp and err will both have a value, so in this case we don't want to retry as it will never succeed.
+				if err == nil && !ResponseHasStatusCode(resp, codes...) || IsTokenRefreshError(err) {
 					return resp, err
 				}
 				delayed := DelayWithRetryAfter(resp, r.Cancel)
 				if !delayed {
 					DelayForBackoff(backoff, attempt, r.Cancel)
 				}
+				// don't count a 429 against the number of attempts
+				// so that we continue to retry until it succeeds
+				if resp == nil || resp.StatusCode != http.StatusTooManyRequests {
+					attempt++
+				}
 			}
 			return resp, err
 		})
@@ -237,6 +244,9 @@ func DoRetryForStatusCodes(attempts int, backoff time.Duration, codes ...int) Se
 // DelayWithRetryAfter invokes time.After for the duration specified in the "Retry-After" header in
 // responses with status code 429
 func DelayWithRetryAfter(resp *http.Response, cancel <-chan struct{}) bool {
+	if resp == nil {
+		return false
+	}
 	retryAfter, _ := strconv.Atoi(resp.Header.Get("Retry-After"))
 	if resp.StatusCode == http.StatusTooManyRequests && retryAfter > 0 {
 		select {