title: How to discard TFS merge when you can't check in the target?
body: <p>There's a config file in the branch I want to merge to that is locked against ordinary developers changing it, but the branch I'm working in needs it to be different.  So now I have a changeset with that one file in it.  I want to discard that as a merge candidate from there to the other branch.  When I issue <code>tf merge /discard</code> against it, I end up with a pending change to the target — but when I try to check that in, it complains that the target is locked for check-in by the administrator (which is the whole reason I wanted to discard the merge in the first place!).  How can I proceed?</p>