Fixed link error during export.

ld: file cannot be mmap()ed, errno=22 path=godot-gdextension-test/dylibs/bin/libgdexample.ios.template_debug.universal.framework/libgdexample.ios.template_debug.universal in
'godot-gdextension-test/dylibs/bin/libgdexample.ios.template_debug.universal.framework/libgdexample.ios.template_debug.universal'
clang: error: linker command failed with exit code 1 (use -v to see invocation)

platform/ios/export/export_plugin.cpp

@@ -1196,7 +1196,7 @@ Error EditorExportPlatformIOS::_copy_asset(const Ref<EditorExportPreset> &p_pres
 
 		asset_path = asset_path.path_join(framework_name);
 		destination_dir = p_out_dir.path_join(asset_path);
-		destination = destination_dir.path_join(file_name);
+		destination = destination_dir;
 
 		// Convert to framework and copy.
 		Error err = _convert_to_framework(p_asset, destination, p_preset->get("application/bundle_identifier"));