Fix broken module

This module was broken on version 4.1.5:

`Error: Execution of '/usr/sbin/chown -R fromonesrc:staff /Applications/Textual-4.1.5.app' returned 1: chown: /Applications/Textual-4.1.5.app: No such file or directory`

This fixes the bad package name and spec.

Also will be releasing a 4.2.0. @bbck just a heads up we are using [semver](http://semver.org/) and the version numbers for releases on this module do not (should not) need to match up with released versions of Textual.app.