Fix exporting internal SDL files.

Previously, we would use the current working directory as the SDL file
path. This would crash when we attempted to see if that file is
encrypted.

korman/exporter/outfile.py

@@ -89,7 +89,7 @@ class _OutputFile:
 
             self.mod_time = None
             self.file_path = None
-            if self.id_data is not None:
+            if self.id_data is not None and not self.id_data.is_in_memory:
                 path = Path(self.id_data.filepath)
                 try:
                     if path.exists():