Following up on r1560701, use a common way of creating the relocate target
in the copy_relocate() test.

* subversion/tests/cmdline/copy_tests.py
  (imports): Remove unused import.
  (copy_relocate): Call add_repo_path() instead of add_wc_path().  Test
    repositories should be located under 'svn-test-work/repositories', not
    under 'svn-test-work/working_copies'.  Drop the handmade file:// URI
    construction, because it is no longer necessary.  As a consequence,
    this test now runs against three protocols (file://, svn://, http://),
    which is better, because all of them fail without r1560690.  The
    behavior of this test with file://, however, remains exactly the same.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1600852 13f79535-47bb-0310-9956-ffa450edef68