Follow-up to r1631075: The error codes returned by APR upon missing paths
differs between OSes. We only need to verify that an error has been detected.

Introduce a variant of SVN_TEST_ASSERT_ERROR that will accept any error
that is not an assertion.

* subversion/tests/svn_test.h
  (SVN_TEST_ASSERT_ANY_ERROR): New test macro, copied and adapted from
                               SVN_TEST_ASSERT_ERROR.

* subversion/tests/libsvn_fs/fs-test.c
  (upgrade_while_committing): Test for any error.

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1631129 13f79535-47bb-0310-9956-ffa450edef68