This sort of thing has been tried for as long as people have been growing (ie decades) and everything I've heard, and everything I know about adding flavoring agents to rooted plants indicates that it doesn't work.
Flavor/odoring agents are generally large molecules, and plant roots CANNOT uptake them.
IMO beer is a particularly poor choice for this sort of experiment. Not only is alcohol potentially toxic to plants roots and beneficial soil bacteria, the residual sugars and such in there are likely to attract insects.
If you want your weed to taste like beer, take a sip in between puffs. Or better yet, mix a little dried hops in with your herb.
Hops is a nice fragrant herb in its own right, and not only is it distantly related to cannabis, but some people believe that hops have a psychoactive effect all by themselves.
