Account for file deletion and renaming in Export Presets

Ensure that presets are updated with the latest files when
starting up or opening the Project Export dialog. Fixes the
error where Godot would attempt to export deleted files that
were previously selected.

editor/project_export.cpp

@@ -163,6 +163,7 @@ void ProjectExportDialog::_update_presets() {
 		if (preset->is_runnable()) {
 			name += " (" + TTR("Runnable") + ")";
 		}
+		preset->update_files_to_export();
 		presets->add_item(name, preset->get_platform()->get_logo());
 	}