Fix another small discrepancy related to dynamic typing in our tests.

* subversion/tests/cmdline/svnadmin_tests.py
  (check_hotcopy_fsfs_fsx): Bring a format string and its arguments into
    correlation.  Prior to this changeset, mismatching db/rep-cache.db
    contents would result in printing a "TypeError: %d format: a number is
    required, not tuple" stacktrace instead of an adequate error message.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1618232 13f79535-47bb-0310-9956-ffa450edef68