Buffered events upload on logger dispose fails if there is no logs yet

[MaceWindu]

using Serilog;
using Serilog.Debugging;

internal class Program
{
	static void Main()
	{
		using var logger = new LoggerConfiguration()
			.WriteTo.Seq("http://localhost:5341", bufferBaseFilename: @"<PATH_TO_NOT_YET_CREATED_FOLDER>\logfile")
			.CreateLogger();

		// buffer folder will be created on first log write
		//logger.Information("Create bookmarks folder");

		SelfLog.Enable(msg => logger.Error($"Logger failure: {msg}"));

		// on logger dispose we try to upload buffered data and fail with
		// DirectoryNotFoundException: Could not find a part of the path 'PATH_TO_NOT_YET_CREATED_FOLDER\\logfile.bookmark'
	}
}

Exception while emitting periodic batch from Serilog.Sinks.Seq.Durable.HttpLogShipper: System.IO.DirectoryNotFoundException: Could not find a part of the path '<PATH_TO_NOT_YET_CREATED_FOLDER>\\logfile.bookmark'.
   at Microsoft.Win32.SafeHandles.SafeFileHandle.CreateFile(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options)
   at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize, Nullable`1 unixCreateMode)
   at System.IO.Strategies.OSFileStreamStrategy..ctor(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize, Nullable`1 unixCreateMode)
   at System.IO.Strategies.FileStreamHelpers.ChooseStrategyCore(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize, Nullable`1 unixCreateMode)
   at System.IO.File.Open(String path, FileMode mode, FileAccess access, FileShare share)
   at Serilog.Sinks.Seq.Durable.BookmarkFile..ctor(String bookmarkFilename)
   at Serilog.Sinks.Seq.Durable.FileSet.OpenBookmarkFile()
   at Serilog.Sinks.Seq.Durable.HttpLogShipper.OnTick()

[todthomson]

Looks like a bug @MaceWindu. Thanks for the bug report. We'll take a look asap and report back.