AsyncNonMetaRegionLocator：put Complete CompletableFuture outside lock block

synchronized (tableCache) {
  tableCache.pendingRequests.remove(req);
  // fail the request itself, no matter whether it is a DoNotRetryIOException, as we have
  // already retried several times
  CompletableFuture<?> future = tableCache.allRequests.remove(req);
  if (future != null) {
    future.completeExceptionally(error);
  }
  tableCache.clearCompletedRequests(null);
  // Remove a complete locate request in a synchronized block, so the table cache must have
  // quota to send a candidate request.
  toSend = tableCache.getCandidate();
  toSend.ifPresent(r -> tableCache.send(r));
}