Merge branch 'jk/close-duped-fd-before-unlock-for-bundle'

When "git bundle" aborts due to an empty commit ranges (i.e. resulting in an empty pack), it left a file descriptor to an lockfile open, which resulted in leftover lockfile on Windows where you cannot remove a file with an open file descriptor. This has been corrected. * jk/close-duped-fd-before-unlock-for-bundle: bundle: dup() output descriptor closer to point-of-use