asset:javascript tag doesn't work in IntelliJ GSP pages

[Gage Pollard]

Intellij doesn't allow this tag in any place in the GSP page, showing the following error:

<asset:javascript src="https://cdn.datatables.net/v/dt/dt-1.13.4/datatables.min.js"/>

"Element asset:javascript is not allowed here."

This may be related to #325
-- Which had no solution.