When testing with packing enabled, don't depend on the cwd in the hook script.
When testing with packing enabled, don't depend on the cwd in the hook
script.

Found by: commit_tests.py

* subversion/tests/cmdline/svntest/main.py
  (create_repos):
    Use the absolute path to the repository in the hook script.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion