Revision 1816424

Following up on r1816402, add a whitelist of the supported templated
repository versions to the svnadmin tests that patch the revision files.

The hardcoded manipulations are not valid for higher formats such as v7,
and since they get the revision file paths based on the server_minor_version,
may also break with older prepackaged versions.  Therefore, we limit the
whitelist to v4 and v6.

* subversion/tests/cmdline/svnadmin_tests.py
  (verify_incremental_fsfs, verify_non_utf8_paths): Limit the supported
   prepackaged repository versions to v4 and v6.