Prevent using seq if no seq host is set

src/Vegasco.Server.Api/Common/DependencyInjectionExtensions.cs

@@ -31,7 +31,11 @@ public static class DependencyInjectionExtensions
 
 	private static IHostApplicationBuilder AddBuilderServices(this IHostApplicationBuilder builder)
 	{
-		builder.AddSeqEndpoint("seq");
+		string? seqHost = builder.Configuration.GetConnectionString("seq");
+		if (!string.IsNullOrEmpty(seqHost))
+		{
+			builder.AddSeqEndpoint("seq");
+		}
 
 		return builder;
 	}