Clear current path when deselecting files

[KoBeWi]

Fixes #92867

godot.windows.editor.dev.x86_64_ZLnIosw8vX.mp4

This also fixes a problem where you may end up with a random file selected after project restart, which can result in many uncollapsed folders.

[Mickeon]

This feels like it should be associated to its own method that sets both at once, but I don't know about the internals of this

[KoBeWi]

I counted 2 other places that could use the method. In other cases the path and text are assigned separately, like

godot/editor/filesystem_dock.cpp

Lines 1742 to 1748 in 46c495c

	current_path = p_file.get_base_dir();
	Ref<DirAccess> da = DirAccess::create(DirAccess::ACCESS_RESOURCES);
	while (!da->dir_exists(current_path)) {
	current_path = current_path.get_base_dir();
	}
	current_path_line_edit->set_text(current_path);

so the method would be not very useful.

[Mickeon]

This should've always been the case even if it didn't fix anything

[Repiteo]

Thanks!