test: improve test-vm-cached-data.js

* verify error message by adding 2nd argument to throws in test-assert

PR-URL: https://github.com/nodejs/node/pull/11974


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Daijiro Wachi <daijiro.wachi@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>