fix: async only for themes with a single script.
fix: async only for themes with a single script.

* if there is a single script load it async.

hlmnrmr/liveblog,hlmnrmr/liveblog,superdesk/liveblog,hlmnrmr/liveblog,liveblog/liveblog,hlmnrmr/liveblog,superdesk/liveblog,liveblog/liveblog,liveblog/liveblog,liveblog/liveblog,superdesk/liveblog,liveblog/liveblog,superdesk/liveblog