[22966] Bug #589865 In the report "Budget flow" period it doesn't work ok

Author: Mikhail TSaplin <tsmisher@gmail.com>

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/branches/2.4@22973 57a11ea4-9604-0410-9ed3-97b8803252fd