transaction: fix file descriptor leak for journal.backupfiles
The journal.backupfiles descriptor wasn't being closed. This resulted in
hgsubversion test runs having a bagillion descriptors open, which crashed on
platforms with low open file limits (like OSX).
fixbundle() {
grep -v 'saving bundle' | grep -v 'saved backup' | \
grep -v added | grep -v adding | \
grep -v "unable to find 'e' for patching" | \
grep -v "e: No such file or directory"
}