Allow users to select a Galaxy history when making worklfow and data landing requests

right now we dump users into their last history i think, upon landing in galaxy from brc. it was recently pointed out this can be awkward or confusing, best practice is probably to use a new history for each analysis, etc. but also i could see use cases for wanting to add to an existing history, except not necessarily the last one. it might be good to let ppl choose a history from the brc site as part of their configuration before clicking to launch in galaxy