chore: fix build error

Author: FantasticFiasco

sample/Sink/CustomHttpClient.cs

@@ -14,13 +14,13 @@ public class CustomHttpClient : IHttpClient
 
         public void Configure(IConfiguration configuration) => httpClient.DefaultRequestHeaders.Add("X-Api-Key", configuration["apiKey"]);
 
-        public async Task<HttpResponseMessage> PostAsync(string requestUri, Stream contentStream)
+        public async Task<HttpResponseMessage> PostAsync(string requestUri, Stream contentStream, CancellationToken cancellationToken)
         {
             using var content = new StreamContent(contentStream);
             content.Headers.Add("Content-Type", "application/json");
 
             var response = await httpClient
-                .PostAsync(requestUri, content)
+                .PostAsync(requestUri, content, cancellationToken)
                 .ConfigureAwait(false);
 
             return response;