fix(esp_http_client): fix spurious async open error

Fix esp_http_client_open() often triggering a
spurious HTTP_EVENT_ERROR when is_async=true.

Fixes #16075

Author: bryghtlabs-richard

components/esp_http_client/esp_http_client.c

@@ -1722,11 +1722,17 @@ esp_err_t esp_http_client_open(esp_http_client_handle_t client, int write_len)
     client->post_len = write_len;
     esp_err_t err;
     if ((err = esp_http_client_connect(client)) != ESP_OK) {
+        if (client->is_async && err == ESP_ERR_HTTP_CONNECTING) {
+            return ESP_ERR_HTTP_EAGAIN;
+        }
         http_dispatch_event(client, HTTP_EVENT_ERROR, esp_transport_get_error_handle(client->transport), 0);
         http_dispatch_event_to_event_loop(HTTP_EVENT_ERROR, &client, sizeof(esp_http_client_handle_t));
         return err;
     }
     if ((err = esp_http_client_request_send(client, write_len)) != ESP_OK) {
+        if (client->is_async && errno == EAGAIN) {
+            return ESP_ERR_HTTP_EAGAIN;
+        }
         http_dispatch_event(client, HTTP_EVENT_ERROR, esp_transport_get_error_handle(client->transport), 0);
         http_dispatch_event_to_event_loop(HTTP_EVENT_ERROR, &client, sizeof(esp_http_client_handle_t));
         return err;