Rework the "recover --pre-1.4-compatible" svnadmin test.  Bump the
MINOR_VERSION of the created repository to 3, because FSFS repositories with
MINOR_VERSION = 0 is prohibited since r1494223 (and creating a repository with
MINOR_VERSION = 3 does the same as the 'svnadmin create --pre-1.4-compatible'
call).  Use run_and_verify_svnadmin instead of run_svnadmin so that the test
actually checks the result of the call instead of always reporting false
positive.

* subversion/tests/cmdline/svnadmin_tests.py
  (recover_old): Bump MINOR_VERSION to 3, use run_and_verify_svnadmin instead
    of run_svnadmin.

Patch by: Evgeny Kotkov <evgeny.kotkov{_AT_}visualsvn.com>