svntest: Fix an error handling bug when running 'svnadmin load'.
svntest: Fix an error handling bug when running 'svnadmin load'.

* subversion/tests/cmdline/svntest/actions.py
  (run_and_verify_load): Check actual error output "errput", rather
   than expected error output "expected_stderr", when deciding whether
   to call compare_and_display_lines().

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion