If you're committed to using Stash, I think you're out of luck. There is currently an open ticket to add this feature to Stash. You can vote for that ticket to be resolved if this is an important feature for you, but it has already been open for over a year.
As you mentioned, this can be done locally. Why don't you want the release manager pulling (or fetching) the repository? Atlassian's graphical client SourceTree can make the process quite painless.